Geographic Areas Reference Manual/Chapter 9

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Geographic Areas Reference Manual
the U.S. Census Bureau
3602359Geographic Areas Reference Manualthe U.S. Census Bureau

Chapter 9

Places

The Bureau of the Census defines a place as a concentration of population; a place may or may not have legally prescribed limits, powers, or functions. This concentration of population must have a name, be locally recognized, and not be part of any other place.

A place either is legally incorporated under the laws of its respective State, or a statistical equivalent that the Census Bureau treats as a census designated place (CDP). Each State enacts laws and regulations for establishing incorporated places. The Census Bureau designates criteria of total population size, population density, and geographic configuration for delineating CDPs. Not everyone resides in a place; in 1990, approximately 66 million people (26 percent) in the United States lived outside of any place, either in small settlements, in the open countryside, or in the densely settled fringe of large cities in areas that were built-up, but not identifiable as places.

The greater number of places reported in the decennial censuses (19,289 out of a total of 23,435 in 1990) are incorporated. Most of these incorporated places have active governments; that is, they have either elected or appointed officials, usually raise revenue, and perform general-purpose local government functions. Incorporated places that have inactive governments generally do not have officials or provide governmental services, but, like active places, they do have legally established corporate limits, and may choose to reactivate at any time. The Census Bureau includes, in the decennial census, all active incorporated places and inactive incorporated places for which it has certified corporate limits as of January 1 of the census year (the date used to tabulate the census results).

The Census Bureau recognized 4,146 CDPs for the 1990 decennial census. These entities, though containing nearly 30 million people, have no separate governments, although most of their residents receive governmental services from county, minor civil division (MCD), special regional or nearby municipal governments. CDPs usually physically resemble incorporated places in that they contain a residential nucleus, have a closely spaced street pattern and frequently have commercial or other urban types of land use. The Census Bureau relies on the assistance of local census statistical areas committees (CSACs), various State authorities, and other organizations to identify potential CDPs and update existing ones. This chapter contains separate discussions of incorporated places and census designated places.

Incorporated Places
Characteristics of Incorporated Places

Incorporated places are established under the authorization of the governments in each of the 50 States. Requirements for incorporation vary widely among the States; some States have few specific criteria, while others have established population thresholds and occasionally other conditions (for example, minimum land area, population density, and distance from other existing incorporated places) that must be met for incorporation (see Table 9-1). The Census Bureau recognizes incorporated places in all States except Hawaii; for Hawaii, by agreement with the Office of the Governor, the Census Bureau recognizes all places as CDPs rather than as incorporated places. Puerto Rico and several of the Outlying Areas under United States jurisdiction (Guam, the Northern Mariana Islands, and Palau) also have no incorporated places (for details, see Chapter 7, “Puerto Rico and the Outlying Areas”).

Different States recognize a variety of entities as incorporated places. Usually, the designations city, town, village, and borough are most frequent; however, one or more places in Kentucky, Montana, Nevada, and Tennessee have place-type governments (usually consolidated ones) that do not fit any of these designations. New Jersey is the only State that has all four kinds of incorporated places. Only two other States (Connecticut and Pennsylvania) include boroughs as incorporated places, 11 States have only cities, and the remainder of the States have various combinations of city, town, and village (see Table 9-1).

The terms town and borough do not always refer to places. In the six New England States, and in New York and Wisconsin, the term town refers to an MCD rather than a place. The MCDs in these States, while often functioning with all the powers of city governments, usually contain considerable rural area; other units of government perform the incorporated place function. In Alaska, the term borough refers to territory governed as a county rather than as a place; in New York, the Census Bureau treats the five boroughs that comprise New York city as MCDs.

Table 9-1. State Requirements for Incorporated Places

Alabama City Minimum population requirement of 2,000.

Town Minimum population requirement of 300; territory located in Jefferson County, or within 3 miles of an incorporated area, requires a population ≥ 1,000 to incorporate; territory in Jefferson County and within 3 miles of an incorporated area requires ≥ 10,000 people to incorporate.
Alaska City No minimum population requirement, but approval of Alaska Department of Community Affairs is required.
Arizona City Minimum population requirement of 1,500.
Town Same requirements as for a city.
Arkansas City Minimum population requirement of 500.
Town Must have ≥ 20 qualified voters to incorporate.
California City Minimum of 500 registered voters to incorporate.
Town Same requirements as for a city.
Colorado City Minimum population requirement of 2,000.

Town Petition must be signed by ≥ 40 registered voters in counties with < 25,000 people, and ≥ 150 registered voters in counties with a population ≥ 25,000. Population density must be ≥ 50 people per square mile.
Connecticut City Incorporation is by special act of the State legislature; there is no minimum population requirement.
Borough Same requirements as for a city.
Delaware
City Incorporation is by special act of the State legislature; there is no minimum population requirement, except for home-rule cities, which require a minimum of 1,000 inhabitants.
Town Incorporation is by special act of the State legislature; there is no minimum population requirement.
Village Same requirements as for a town.
District of Columbia City No minimum population requirement; has a single incorporated place covering its entire area.
Florida
City In counties with < 50,000 residents, at least 1,500 residents are required for incorporation; in other counties, at least 5,000 residents are required. Population density must be ≥ 1.5 people per acre, except under extenuating circumstances.
Town Same requirements as for a city.
Village Same requirements as for a city.
Georgia City Total population must ≥ 200, and population density must be ≥ 200 people per square mile.
Town Same requirements as for a city.
Hawaii None Hawaii has no incorporated places, only CDPs; the Census of Governments counts the combined city and county of Honolulu as a municipality; other censuses recognize the Honolulu judicial district as a separate place within the county.
Idaho City A minimum of 125 qualified voters to incorporate.
Illinois
City Minimum population requirement of 2,500; if located in Cook County, may incorporate with a minimum of 1,200 residents if the area consists of less than 4 square miles and contains all the registered voters of a township not already within the corporate limits of a municipality.
Town No minimum population requirement.
Village If counties with a population ≥ 150,000, a minimum of 2,500 residents are required to incorporate; a minimum of 200 residents are required in other counties.
Indiana City If a town has a minimum of 2,000 inhabitants, it may hold a referendum on conversion to city status.
Town A petition signed by > 50 landowners is needed to incorporate.
Iowa City No minimum population requirement, but approval of the State City Development Board is required.
Kansas City A population ≥ 300, or territory containing ≥ 300 platted lots, each served by water and sewer lines owned by a non-profit corporation, and a petition signed by at least 50 registered voters are required for incorporation; there are no minimum population requirements if the territory has been designated a national landmark by the U.S. Congress.
Kentucky City Minimum population requirement of 300.
Louisiana City Minimum population requirement of 5,000.
Town Minimum population requirement of 1,000.
Village Minimum population requirement of 300.
Maine City Incorporation is by special act of the State legislature; there is no minimum population requirement.
Maryland City Minimum population requirement of 300.
Town Same requirements as for a city.
Village Same requirements as for a city.
Massachusetts City Minimum population requirement of 12,000.
Michigan
City Minimum population requirement of 750, except home-rule cities, which require a minimum population of 2,000 and a population density ≥ 500 people per square mile.
Village Minimum population requirement of 250 and a minimum area of 3/4 square mile, unless situated in the upper peninsula.
Minnesota City No minimum population requirement, but approval of the Minnesota Municipal Board is necessary.
Mississippi[9-1 1]


City Minimum population requirement of 2,000.
Town Minimum population requirement of 300.
Village Under current Mississippi law, new villages may no longer be incorporated. Those that incorporated before this law was enacted needed a population > 100 and < 300 to maintain their incorporated status (villages that fall below a population of 100 are decertified by the State, reverting to unincorporated status).
Missouri City Minimum population requirement of 500.
Town No minimum population requirement.
Village No minimum population requirement; a village, once incorporated, may choose to become a city if it has a population ≥ 200.
Montana City Minimum population requirement of 1,000.

Town Minimum population requirement of 300, and a population density ≥ 500 people per square mile, unless the community was a town site owned and built by the U.S. Government prior to April 3, 1981.
Nebraska City Minimum population requirement of 800.
Village Minimum population requirement of 100.
Nevada
City Minimum requirement of 250 voters; minimum population density requirement of 4 people per acre if the city is within 7 miles of a county seat, or within 7 miles of another city at least equal to the density of the proposed city; otherwise, there are no density requirements. These requirements do not apply to special charter cities.
Town Same requirements as for a city.
New Hampshire City Incorporation is by special act of the State legislature; there is no minimum population requirement.
New Jersey City Incorporation is by special act of the State legislature; there is no minimum population requirement.
Town Same requirements as for a city.
Village Same requirements as for a city.
Borough Same requirements as for a city.
New Mexico
City Minimum population requirement of 150, and the population density must be at least one person per acre, except in Hidalgo and Sierra counties where the density must be 1 person per 4 acres.
Town Same requirements as for a city.
Village Same requirements as for a city.
New York City Incorporation is by special act of the State legislature; there is no minimum population requirement.
Village Minimum population requirement of 500 and must have a population density of ≥ 100 people per square mile.
North Carolina City Incorporation is by special act of the State legislature; there is no minimum population requirement.
Town Incorporation is by special act of the State legislature; there is no minimum population requirement.
Village Incorporation is by special act of the State legislature; there is no minimum population requirement.
North Dakota City No minimum population requirement; the total territory of a city may not exceed 4 square miles and the population density must be ≥ 100 people per square mile.
Ohio


City Minimum population requirement of 25,000 for new cities; existing cities have a minimum population requirement of 5,000. Cities must be at least 4 square miles in area, have a minimum population density of 1,000 people per square mile, and an assessed property valuation of $2,500 per capita.
Village Minimum population requirement of 1,600, a minimum population density requirement of 800 people per square mile, and an assessed property valuation of at least $3,500 per capita.
Oklahoma City Minimum population requirement of 1,000.
Town Petition signed by ≥ 25 registered voters needed to incorporate.
Oregon City Minimum population requirement of 150.
Town Same requirements as for a city.
Pennsylvania City Minimum population requirement of 10,000.
Town No minimum population requirement.
Borough No minimum population requirement.
Rhode Island City Incorporation is by special act of the State legislature; there is no minimum population requirement.
South Carolina

City No minimum population requirement; a minimum density of 300 people per square mile is required, except for (1) areas bordering on or being within 2 miles of the Atlantic Ocean, and (2) areas on all sea islands bounded on at least one side by the Atlantic; both require a minimum of 150 dwelling units, at least 1 dwelling unit per 3 acres, and 50 resident voters.
Town Same requirements as for a city.
South Dakota City Minimum requirement of 100 people or 30 registered voters; historical and educational municipalities require 1 resident to incorporate.
Town Same requirements as for a city.
Tennessee
City Minimum population requirement of 500, except cities under the manager-council form of government, which require a population of ≥ 5,000 to incorporate.
Town Same requirements as for a city.
Texas[9-1 2]
City Minimum population requirement of 600 if organized under 1875 legislation, or 201 if organized under 1909 legislation.
Town Same requirements as for a city.
Village Minimum population requirement of 201.
Utah City Minimum population requirement of 800.
Town Population requirement ≥ 100 and ≤ 800.
Vermont City Incorporation is by special act of the State legislature; there is no minimum population requirement.
Village Must contain 30 or more houses.
Virginia City Minimum population requirement of 5,000.
Town Minimum population requirement of 1,000.
Washington

City Minimum population requirement of 1,500; territory within 5 air miles of a city whose population is >15,000 requires a minimum population of 3,000 to incorporate.
Town Minimum population requirement of 300; territory within 5 air miles of a city whose population is >15,000 requires a minimum population of 3,000 to incorporate.
West Virginia

City Minimum population requirement of 2,001.
Town Towns of 1 square mile or less require 100 residents to incorporate; otherwise at least 500 residents are required.
Village Same requirements as for towns.
Wisconsin City Minimum requirements for isolated cities are a population of 1,000, an area ≥ 1 square mile, and a population density of ≥ 500 people per square mile; metropolitan cities are those that are situated in a county containing two cities with an aggregate population ≥ 25,000; metropolitan cities require a population of ≥ 5,000, an area of ≥ 3 square miles, and a population density of ≥ 750 people per square mile.
Village Minimum population requirement for isolated villages is 150; metropolitan villages are those that are situated in a county containing two cities with an aggregate population of ≥ 25,000; metropolitan villages require a population of ≥ 2,500, an area of ≥ 2 square miles, and a density of ≥ 500 people per square mile.
Wyoming City Minimum population of 500 within an area of 3 square miles or less is required to incorporate.
Town Same requirements as for a city.
  1. Cities, towns, and villages may be incorporated, regardless of population, in an area not less than 1 square mile wherein there is in existence or under construction not less than 1 mile of hard surface streets, with a total of not less than 6 streets, and there exists, or is under construction, a public utilities system that includes a waterworks or sewerage system, or both.
  2. Cities, towns, and villages with a population below 2,000 may not have an area over 2 square miles. A municipality whose population is between 2,000 and 4,999 may not have an area greater than 4 square miles, and those whose population is between 5,000 and 9,999 may not have an area in excess of 9 square miles. Home-rule municipalities require a population of at least 5,000.

Note: The information in this table is based on research of State statutes by the Governments Division of the Census Bureau and is current through 1990. Some of this information may be superseded by subsequent legislative acts.

Relationships of Incorporated Places to Other Geographic Entities

Incorporated places have legally prescribed relationships with governmental entities such as States, counties, and MCDs. Incorporated places have geographic relationships with nongovernmental statistical entities such as census tracts, block numbering areas (BNAs), block groups and census blocks, census county divisions (CCDs), and urbanized areas (UAs). The geographic hierarchy shows the interrelationships of these entities to places (see Figures 2-1 and 2-2 in Chapter 2, “Geographic Overview”).

States and counties

Because incorporated places are chartered by States, no place may extend into more than one State. Thus, cities of the same name that might appear to be one are each distinct geographic entities. Examples include Kansas City, Missouri, and Kansas City, Kansas; Texarkana, Arkansas, and Texarkana, Texas; and Bristol, Virginia, and Bristol, Tennessee.

In most States, multi-county places are common; however in the New England States and the States of California, Montana, Nevada, and New Jersey, incorporated places do not cross county lines. In Virginia, the 41 cities are independent of any county, and the Census Bureau treats them as the statistical equivalents of counties; also, there is one independent city each in Maryland (Baltimore), Missouri (St. Louis), and Nevada (Carson City).

County subdivisions

Incorporated places have varying relationships with county subdivisions in their respective States. In 21 States, the Census Bureau, in cooperation with State officials and the census statistical areas committees, has designated census county divisions (CCDs). These have no governmental or administrative functions, and incorporated places in these States appear as dependent within the CCDs; that is, in statistical tables, the data for the places also are included in the totals for the CCDs, and the place names appear indented under the CCD names. Places may be located in more than one CCD.

In the remaining States, the county subdivisions are MCDs. Some of the MCDs have strong governments (in some States, they perform functions identical or similar to those of incorporated places). Others have governments performing few if any functions, or no governments whatsoever, as is the case with unorganized territories, the election districts of Maryland, the magisterial districts of Virginia, and similar units. All incorporated places within a State may be independent of any MCD (as in Wisconsin), dependent within an MCD (as in Mississippi), or there may be a mixture of independent and dependent incorporated places (for example, in Vermont, villages are dependent within MCDs, while cities are independent of any MCD). Dependent places frequently are located in more than one MCD.

The places that are independent of any county subdivision stand alone in the Census Bureau’s statistical presentations; that is, they appear in the same alphabetical format within counties as the MCDs, and their statistical information is not included in that of another entity except the county. Although they are not shown as part of any MCD, the Census Bureau assigns these places MCD geographic identification codes so that there is complete county subdivision coverage for the entire United States. (For details, see the “Place Codes” section at the end of this chapter.)

There are complex place/MCD relationships in several States. For example, in Ohio, places that are in more than one county may be independent of any MCD in one county, yet be dependent within an MCD in another county. In some States, there are some places that are coextensive with one or more MCDs. When these places annex or detach territory, the MCD boundary automatically changes with the place boundary, adding area from or losing area to, surrounding MCDs. (For further information on the geographic relationships between places, MCDs, and CCDs, refer to Chapter 8, “County Subdivisions,” specifically Table 8-4, which describes the relationship of places to county subdivisions in each State.)

Relationships to other geographic entities

Census Bureau criteria that establish the relationships of incorporated places to the statistical entities generally do not vary among the States. For the 1990 census, places consisted of whole census blocks. When a place boundary split a previously existing census block, the split block number was assigned suffixes, with each suffixed part representing a new block (see Chapter 11, “Census Blocks and Block Groups”). The boundaries of census tracts, BNAs, and block groups generally do not follow incorporated place boundaries because place boundaries are subject to frequent change, whereas census tracts and BNAs are designed to be essentially stable units for intercensal data comparisons (see Chapter 10, “Census Tracts and Block Numbering Areas”). An exception is the use of incorporated place boundaries as census tract, BNA, and block group boundaries in States of the Northeast; another exception occurs where there are conjoint (shared) boundaries between two incorporated places. Urbanized areas include whole CDPs, and generally include whole incorporated places except in the case of extended cities (see the “Extended Cities” section in this chapter).

Places and the Urban and Rural Classifications

At one time, places were the only geographic units the Census Bureau used for determining the urban and rural populations and areas of the United States. Before 1950, the Census Bureau classified incorporated places having 2,500 or more residents as urban; it classified all smaller incorporated places, together with nonplace territory, as rural. In addition to incorporated places, the Census Bureau designated certain densely settled MCDs as urban places. For 1950, the Census Bureau introduced urbanized areas (UAs) to better define large agglomerations of population (see Chapter 12, “The Urban and Rural Classifications”). It also introduced census designated places (CDPs), then known as unincorporated places. These two measures provided a better classification of densely developed area outside of incorporated places.

Large-area incorporated places

Incorporated places vary greatly in population, in physical extent, in the stability of their boundaries, and in their usefulness as a measure of the urban population of an area. The largest incorporated place in the Nation has more than seven million inhabitants, the smallest, fewer than ten. The largest incorporated place, in areal measure, has more than 2,800 square miles; the smallest, a few acres. (Table 9-2 lists the places that encompass more than 100 square miles of land.)

Table 9-2. Places of More Than 100 Square Miles on January 1, 1990

Place Name State Land Area
(sq. mi.)
Sitka AK 2,881.49
Juneau AK 2,593.57
Anchorage AK 1,697.65
Jacksonville (consolidated city) FL 773.85
Anaconda–Deer Lodge[9-2 1] MT 736.94
Butte–Silver Bow (consolidated city) MT 718.33
Oklahoma City OK 608.16
Houston TX 539.88
Nashville (consolidated city)[9-2 2] TN 502.26
Los Angeles CA 469.34
Skagway AK 454.68
Phoenix AZ 419.91
Suffolk VA 400.08
Indianapolis (consolidated city) IN 366.81
Dallas TX 342.41
Chesapeake VA 340.68
San Antonio TX 333.04
San Diego CA 324.01
Kansas City MO 311.54
New York NY 308.95
Lexington–Fayette KY 284.52
Fort Worth TX 281.08
Memphis TN 256.05
Virginia Beach VA 248.33
El Paso TX 245.36
Chicago IL 227.23
Valdez AK 218.82
Austin TX 217.78
Columbus (consolidated city) GA 216.31
Columbus OH 190.93
California City CA 184.60
Scottsdale AZ 184.37
Tulsa OK 183.52
Colorado Springs CO 183.19
Hibbing MN 181.68
New Orleans LA 180.65
Norman OK 177.03
Charlotte NC 174.26
San Jose CA 171.26
Huntsville AL 164.60
Tucson AZ 156.29
Denver CO 153.28
Birmingham AL 148.49
Carson City NV 143.55
Sierra Vista AZ 142.37
Detroit MI 138.72
Philadelphia PA 135.13
Montgomery AL 134.98
Corpus Christi TX 134.97
Aurora CO 132.53
Albuquerque NM 132.20
Atlanta GA 131.78
Lynchburg, Moore County TN 129.17
Portland OR 124.66
Chattanooga TN 118.43
Mobile AL 118.03
Columbia SC 117.14
Wichita KS 115.14
Goodyear AZ 115.04
Salt Lake City UT 109.02
Jackson MS 109.01
Tampa FL 108.68
Mesa AZ 108.59
Kansas City KS 107.79
Babbitt MN 105.66
Cape Coral FL 105.12
Unalaska AK 104.27
Lubbock TX 104.11
Abilene TX 103.09
Little Rock AR 102.86
Omaha NE 100.65
  1. Official name is Anaconda–Deer Lodge County.
  2. Official name is Nashville–Davidson.
Note: Multiply square miles by 2.59 to convert to square kilometers.
There are incorporated places, particularly in the Northeast, that have not had a boundary change this century; there are a few places in Alabama and California that have, in recent years, had boundary changes virtually every month.

There is only a limited relationship between place size and place population, and the relationship seems to vary by region. The most densely settled places generally are the older cities in the Northeast region, cities that underwent early development and tend to have relatively fixed boundaries. In the Northeastern States, the MCDs have strong governments that often have all the powers associated with incorporated places; as a consequence, annexation for the purpose of providing municipal services is unnecessary, and in some States is difficult, if not impossible. In some Midwestern and Southern States, boundary change laws are more permissive, and aggressive or widespread annexations often result in lower population densities for places.

Extended cities

Recognizing the effects of city/county consolidations and unrestricted annexation practices in some States, the Census Bureau developed the extended city concept for the 1970 census. This concept modified the urban and rural classifications by defining, within UAs, certain sparsely settled portions of large-area incorporated places as rural. In 1980, after identifying extended cities in UAs, there still were nine sparsely settled incorporated places outside UAs that contained almost 7,700 square miles of territory, an area larger than the State of New Jersey. This distorted the national percentage of urban area by nearly 10 percent. To correct this situation for 1990, the Census Bureau modified the extended city criteria to include non-UA incorporated places. (For further information on extended cities, both inside and outside of UAs, see Chapter 12.)

Changes in the Boundaries and Status of Incorporated Places

Incorporated place boundaries are subject to change; in some States, many do so frequently. The instruments of change are municipal annexation and detachment, merger or consolidation, and incorporation and disincorporation. Beginning in 1970, the Census Bureau recognized boundaries legally in effect on January 1 of the census year, rather than April 1 (census day) to tabulate the results of its decennial censuses. This enabled the Census Bureau to avoid last-minute updates and revisions of boundaries and to put its efforts into field enumeration, processing of results, and preparation for data tabulations—all under extremely stringent time constraints.

Annexations and detachments

Annexation is the legal expansion of corporate limits. It commonly involves the transfer of territory outside the jurisdiction of any municipal-type government into an incorporated place, but it also may involve a transfer of land between two or more incorporated places. In the Northeastern States and parts of the Midwest, annexations by some incorporated places transfer land between governmental entities (from the jurisdiction of MCDs to places). Detachment is the reverse of annexation, whereby an incorporated place relinquishes territory to another jurisdiction. Detachments occur considerably less frequently than do annexations.

Annexation practices vary greatly among the States. In some States, incorporated places merely file ordinances and immediately take over new territory; in others, there are annexation elections involving voters of both the annexing place and the territory proposed for annexation. Still other States establish a period of time over which the municipal government bringing the boundary change action must demonstrate that it can supply or improve upon the governmental services existing in the territory proposed for annexation. In some States, annexation or detachment actions do not become effective until a specified time after enactment. Differing State laws, intergovernmental relationships, political power balances, historic settlement patterns, and customary practices resulted in variations by State in the percentage of incorporated place boundary changes in the 1980 to 1990 period from zero in most of the New England States to over 80 percent in California (see Table 9-3).

Mergers
Mergers represent the combination of two or more governmental units into one. They usually involve like governments, most often incorporated places, but occasionally represent the combination of an incorporated
Table 9-3. Incorporated Places With Boundary Changes, by State, From 1980 to 1990
Boundary Activity Places Percent
Change
(annexed) (detached) (both) (total) (changed)
Alabama 192 4 31 439 227 51.7
Alaska 27 1 0 152 28 18.4
Arizona 57 0 8 86 65 75.6
Arkansas 201 2 2 487 205 42.1
California 278 12 76 456 366 80.3
Colorado 134 0 27 267 161 60.3
Connecticut 1 0 0 31 1 3.2
Delaware 23 0 0 57 23 40.4
District of Columbia 0 0 0 1 0 0.0
Florida 193 2 34 390 229 58.7
Georgia 252 1 21 535 274 51.2
Hawaii 0 0 0 0 0 0.0
Idaho 66 3 15 200 84 42.2
Illinois 524 21 73 1,279 618 48.3
Indiana 221 1 15 566 237 41.9
Iowa 202 11 10 953 223 23.4
Kansas 209 5 26 627 240 38.3
Kentucky 169 4 14 438 187 42.7
Louisiana 142 2 7 301 151 50.2
Maine 0 0 0 22 0 0.0
Maryland 75 3 2 155 80 51.6
Massachusetts 0 0 0 39 0 0.0
Michigan 184 4 22 534 210 39.3
Minnesota 223 30 35 854 288 33.7
Mississippi 92 1 2 295 95 32.2
Missouri 294 7 15 942 316 33.5
Montana 45 4 9 128 58 45.3
Nebraska 122 11 10 535 143 26.7
Nevada 8 0 2 18 10 55.6
New Hampshire 0 0 0 13 0 0.0
New Jersey 8 3 1 320 12 3.8
New Mexico 56 0 1 98 57 58.2
New York 101 2 4 619 107 17.3
North Carolina 284 0 9 511 293 57.3
North Dakota 68 2 6 366 76 20.8
Ohio 309 8 16 941 333 35.4
Oklahoma 200 16 56 592 272 45.9
Oregon 132 3 7 241 142 58.9
Pennsylvania 11 1 5 1,022 17 1.7
Rhode Island 0 0 0 8 0 0.0
South Carolina 134 1 4 270 139 51.5
South Dakota 65 4 4 310 73 23.5
Tennessee 197 3 15 336 215 64.0
Texas 475 17 133 1,171 625 53.4
Utah 102 2 22 228 126 55.3
Vermont 1 1 0 51 2 3.9
Virginia 42 1 6 229 49 21.4
Washington 183 1 3 266 187 70.3
West Virginia 74 1 1 230 76 33.0
Wisconsin 267 3 30 583 300 51.5
Wyoming 54 0 2 97 56 57.7
 
U.S. Totals 6,697 198 781 19,289 7,676 39.8
Source: P.L. 94-171 Redistricting Data File.
place and an MCD, such as the 1986 merger of Northampton township, Ohio, into Cuyahoga Falls city. Typically, the name of the preexisting largest entity is adopted for the one remaining government, but occasionally, the names of both merging entities are combined to represent the surviving government, or the entity adopts an altogether new name. In an unusual four-place merger that took place in January 1994, the cities of Flat River, Elvins, Esther, and the village of Rivermines, Missouri, joined to form the new place of Park Hills.
Consolidated cities

Although the term consolidation sometimes is used interchangeably with merger, the Census Bureau generally uses consolidation to describe the creation of a new type of government resulting from an agreement between a city, its surrounding county, and any other governmental units within that county. The term consolidation is used when different levels of government are represented by a single entity; this new type of government has jurisdiction over the entire county or MCD area, unless some preexisting places are specifically excluded, as is the case with Lawrence, Beech Grove, Speedway, and Southport, Indiana, which have no governmental association with Indianapolis, Indiana. The Census Bureau defines a consolidated city as one wherein an additional incorporated place or places continue(s) to exist. In 1990, there were six consolidated cities: Butte–Silver Bow, Montana; Columbus, Georgia; Indianapolis, Indiana; Jacksonville, Florida; Milford, Connecticut; and Nashville–Davidson, Tennessee. In 1991, Athens–Clarke County, Georgia, became a consolidated city. All of these consolidated cities represent city–county consolidations except Milford, Connecticut, which is the consolidation of a city and an MCD.

For the 1990 census, the Census Bureau reported the population of the smaller incorporated places that continue to exist within the consolidation as separate from the principal city, which is described as remainder in the data tables. The Census Bureau treats each entity with the remainder designation as a separate place; the consolidated government is not treated as a place, but as a separate consolidated city entity in the data presentation.

In the 1980 census, the Census Bureau also excluded the other separate incorporated places that were part of the consolidated city from the population count of the principal city (but did not use the term remainder in its title); in 1970, it included them in the principal city’s population count, but erroneously did not report data for the separately incorporated places that continued to exist within the consolidated city.

Relatively few city–county consolidations with dependent places have arisen since 1960, although there are a number of older city–county consolidations with only a single surviving city; for example, New Orleans, Louisiana; Philadelphia, Pennsylvania; San Francisco, California; and New York, New York, where the city consolidated with five counties.

Attributes of incorporated place boundaries

Corporate limits may have unique boundary features that are irregular in shape. Some States allow incorporated places to annex area that is not contiguous to the existing corporate limits. Some places annex narrow strips of land that often are unpopulated (for example, highway rights-of-way); the Census Bureau calls the latter areas corporate corridors and may display them on its map products by using a special mapping symbol.

The Boundary and Annexation Survey

In order to obtain better intercensal records of place incorporations, disincorporations, mergers, annexations, detachments, and changes affecting counties, the Census Bureau began an annual Boundary and Annexation Survey (BAS) in 1972. In most years the Census Bureau mails the BAS to each county (or equivalent governmental entity, such as the parish in Louisiana and the borough in Alaska), plus any incorporated places above a certain population size (usually 5,000 or more). The BAS is mailed to all incorporated places (and MCDs) in selected years, including the three-year period immediately before each decennial census. The BAS also provides a record of changes to place names and corporate status (that is, city, town, village, borough), an annual update of the universe of incorporated and active places, as well as information on boundary changes. The Census Bureau then provides all the BAS information to a representative of the State government—the State certifying official—for confirmation and certification.

The Census Bureau’s computerized geographic data base of the entire Nation, the TIGER data base, stores information about features (such as roads, rivers, lakes, railroads, and power lines) and boundaries, along with information about the relationships among them. Since 1988, the Census Bureau has produced, from its TIGER data base, digital maps for the BAS. All information obtained through the BAS is then entered into the TIGER data base so that all subsequent TIGER System products reflect these changes.

Census Designated Places

Census designated places (CDPs) are communities that lack separate governments but otherwise resemble incorporated places. They are settled population centers with a definite residential core, a relatively high population density, and a degree of local identity. Often a CDP includes commercial, industrial, or other urban types of land use. Before each decennial census, CDPs are delineated by State and local agencies, and by tribal officials according to Census Bureau criteria. The resulting CDP delineations are then reviewed and approved by the Census Bureau. The Census Bureau has used slightly different definitional criteria for CDPs, depending on their geographic location; such specialized criteria reflect the uniquely different living conditions or settlement patterns found in certain areas and the relative importance of settlement size. Examples are the CDPs inside UAs and outside of UAs, and the CDPs in Alaska, Hawaii, Puerto Rico, the Outlying Areas, and on American Indian reservations (for details, see the section in this chapter entitled “Criteria for Delineation of CDPs in the 1990 Census”). Although only about one-fifth as numerous as incorporated places, CDPs are important geographic units; they permit the tabulation of population counts for many localities that otherwise would have no identity within the Census Bureau’s framework of geographic areas. In 1990, over 29 million people in the United States resided in CDPs (see Table 9-4).

Table 9-4. CDPs and Incorporated Places in the U.S., 1950 Through 1990

Number Population Percent
Population
1950 CDPs 01,430 003,565,496 02.3
Incorporated Places 17,118 096,062,627 63.7
1960 CDPs 01,576 006,583,649 03.7
Incorporated Places 18,088 115,910,865 64.6
1970 CDPs 02,102 012,816,101 06.3
Incorporated Places 18,666 131,931,660 64.9
1980 CDPs 03,432 024,176,786 11.1
Incorporated Places 19,097 140,273,938 61.9
1990 CDPs 04,146 029,595,737 11.9
Incorporated Places 19,289 152,942,266 61.5

Note: Table 9-4 above reflects the unincorporated place/CDP criteria applied at the time of each decennial census. In 1940, there were 3,594 “unincorporated communities,” but no total population was compiled or published. The 1950 information refers to the coterminous 48 States. From 1960 to 1990, CDP totals include Alaska and Hawaii; incorporated place totals do not include Hawaii since the Census Bureau treats all places there as CDPs.

Origin and Evolution of CDPs

At the time of the early decennial censuses, there were sharper distinctions than now exist between city and country, or place and nonplace populations. The United States was largely agrarian; modern-day utilities and transportation systems did not exist. Thus, the communities that did exist tended to be compact, densely settled, easily identifiable, and of relatively great economic and cultural significance. Nonetheless, early census-taking procedures tended to be casual—there was no systematic effort to report the population by place—and many incorporated communities were not identified specifically. Despite an increased awareness of the need for a more precise accounting of the distribution of the population, a systematic, separate, and detailed reporting of the incorporated place population did not begin until the 1880 census. That census also marked the first systematic identification and reporting of unincorporated communities, which appeared in separate tables for each State.

Some unincorporated places first were reported in statistical tables in the 1850 census, usually appearing under the appropriate MCDs. After the clarification and expansion of this reporting in 1880, the 1890 decennial census intermingled incorporated and unincorporated places without distinguishing them. The next four decennial censuses did not include unincorporated communities.

For the 1940 decennial census, the Census Bureau compiled a separate report of unofficial, unincorporated communities of 500 or more people. The Census Bureau identified many of the communities in advance with mapping assistance from the U.S. Public Roads Administration, but also relied on census enumerators to identify and approximate the boundaries of additional communities. Many of the unincorporated communities included in the special 1940 report were not communities in the sense of being cohesive, locally recognized settlements; rather, they often were merely residential subdivisions or clusters of housing units.

The Census Bureau officially recognized unincorporated places in the decennial census of 1950, identifying all potential areas in advance of the count, including them on census maps, and adding them to its geographic coding framework. It established a population minimum of 1,000 and used the symbol (U) to identify them in the decennial census reports of 1950, 1960, and 1970. This designation changed to CDP in the 1980 census.

Many of the residential subdivisions included in the 1940 Unincorporated Communities report were included in the new urban fringe delineations in the 1950 census without separate identification. Unincorporated places were not identified within UAs until the 1960 census, when the Census Bureau established a 10,000 person population minimum. The Census Bureau has modified the population threshold for identifying unincorporated places within UAs with each subsequent decennial census to the present time; however, the 1,000 population minimum outside of UAs has been constant, with the exception of Alaska, Hawaii, Puerto Rico, and places within American Indian reservations (see Table 9-5). Beginning with the 1970 census, the Census Bureau recognized as unincorporated places, the concentrated residential populations on and around military installations.

Table 9-5. Criteria for Qualification of CDPs From 1940 Through 1990

1940 No official recognition of CDPs as places; unincorporated communities of 500 or more inhabitants were tabulated when separate figures could be compiled.
1950 Outside of UAs, unincorporated places of 1,000 or more inhabitants qualified as CDPs.

Inside UAs, only incorporated places were recognized.

1960 Outside of UAs, 1,000 or more inhabitants were required to qualify a place as a CDP.

Inside UAs, unincorporated places of 10,000 or more inhabitants were recognized as CDPs. No unincorporated places in New England UAs could be included in the UA.

1970 Outside of UAs, 1,000 or more inhabitants were required to qualify a place as a CDP.

Inside UAs, unincorporated places (excluding New England UAs) of 5,000 or more inhabitants were recognized as CDPs.

1980 Outside of UAs, 1,000 or more inhabitants were required to qualify a place as a CDP.

Inside UAs, CDPs were recognized if they had 5,000 or more inhabitants (in larger UAs), or 1,000 or more inhabitants (in smaller UAs). This was the first year the Census Bureau recognized CDPs inside New England UAs.

1990 Outside of UAs, 1,000 or more inhabitants (250 or more on American Indian reservations) were required to qualify a place as a CDP.

Inside UAs, CDPs were recognized if they had 2,500 or more inhabitants (a few if they had 1,000 to 2,499 inhabitants).

Note: Since before 1950, the minimum unincorporated place/CDP size for Alaska (outside of UAs) has been 25 or more inhabitants; for Hawaii (both inside and outside of UAs) it has been 300 or more.

For the 1980 census, the Census Bureau changed the name unincorporated place to census designated place in order to emphasize that these communities are described and delineated by the Census Bureau (albeit with State and local input), and do not represent an unabridged list of communities that lack legal definition. Also, with the advent of the General Revenue Sharing Program in the 1970s, the term unincorporated place had caused some confusion locally. This was particularly true in Northeastern and some Midwestern States where many of the MCDs were incorporated, and where their officials were displeased by the Census Bureau’s classification of any portions of their governments as unincorporated.

The 1980 census included a whole-town CDP category, whereby MCDs in New England, the Middle Atlantic States, Michigan, and Wisconsin were treated as places (for urban/rural qualification and whole-count purposes) if 95 percent or more of their population and 80 percent or more of their land area qualified for inclusion in a UA. The Census Bureau long has grappled with the proper treatment of these strong governmental entities, particularly in the classification of their populations as urban or rural. These MCDs also were treated as places in the 1940, 1960, and some earlier censuses. The Census Bureau dropped the whole-town CDP category for the 1990 census; CDPs defined within these largely built-up MCDs follow regular CDP criteria. That is, the entire MCD may be coextensive with a CDP, or the MCD may contain one or more CDPs. In its 1990 data presentations, the Census Bureau has included the MCDs in 12 States (the 6 New England States plus Michigan, Minnesota, New Jersey, New York, Pennsylvania, and Wisconsin) in some of the data products that present tabulations for places of 2,500 or more. The MCDs in these States serve as general purpose local governments, and they possess legal or governmental powers similar to those of incorporated places. As a result, data users interested in both kinds of entities can refer to them more easily (see Table 9-6).

Table 9-6. Criteria for Qualification of MCDs as Urban Places From 1940 Through 1990

1940 Towns in Massachusetts, New Hampshire, and Rhode Island containing 2,500 or more inhabitants and having densely settled area(s) comprising 50 percent or more of the population qualified as urban under special rule. In other States, MCDs of 10,000 or more inhabitants and with a density of at least 1,000 people per square mile also qualified as urban under special rule.
1950 None
1960 Urban towns in New England, and urban townships in New Jersey and Pennsylvania qualified as urban places if they had no incorporated places, and either (1) 25,000 or more inhabitants or (2) 2,500 to 24,999 inhabitants and a density of at least 1,500 people per square mile.
1970 None
1980 Towns in New England, New York, and Wisconsin, and townships in New Jersey and Pennsylvania qualified as urban places (also called whole-town CDPs) if they had no incorporated places, 1,000 or more inhabitants, and if both 90 percent of the population and 80 percent of the land area met the minimum density requirement for inclusion in a UA.
1990 None
Criteria for Delineation of CDPs in the 1990 Census

The Census Bureau has developed a program whereby local census statistical areas committees, tribal officials, and State-designated agencies identify and delineate boundaries for potential CDPs according to criteria developed by the Census Bureau.

General characteristics

In general, a CDP should be a densely settled and named community or population center that does not have legally defined municipal boundaries or corporate powers. It may not include any portion of an incorporated place. A named subdivision or building complex should not be considered a CDP unless it represents a planned community that offers a range of community facilities and services.

Unlike most incorporated places, CDP boundaries are delineated to follow visible features (streets, roads, rivers, railroads, and the like) except where the boundary of the potential CDP is coincident with the boundary of an adjoining legally recognized entity, such as an incorporated place or MCD. Because of this requirement, sparsely settled area sometimes is included in a CDP, or conversely, a small fringe of built-up area is not included in the CDP. The latter is particularly is true in relatively small CDPs where outlying roads or features that may be used as boundaries are spaced widely.

Ideally, CDPs contain a dense, city-type street pattern and have an overall population density of at least 1,000 people per square mile. However, the Census Bureau recognizes that some CDPs may not meet the density criterion because the selection of available boundary features may result in the CDP including some sparsely settled territory. Another exception to the density criteria may occur on American Indian reservations, where communities often have a dispersed settlement pattern. Several minimum population sizes apply to CDPs recognized in the 1990 census, but there is no maximum limit to the number of people a CDP may contain.

CDPs inside UAs

The minimum population size for most CDPs located within UAs is 2,500. However, because preliminary 1990 population counts were used to qualify CDPs, some CDPs inside UAs have less than 2,500 people. (For details, see Chapter 12, “The Urban and Rural Classifications.”) This 2,500 population size threshold does not apply to Hawaii, Puerto Rico, or the Outlying Areas.

CDPs outside of UAs

The minimum population size for most CDPs located outside of UAs is 1,000 people; for CDPs on American Indian reservations, it is 250 people. These sizes do not apply to Alaska, Hawaii, Puerto Rico, or the Outlying Areas.

CDPs in Alaska

Alaska is by far the most sparsely settled of the States, and has very few communities with more than 1,000 residents. To account for the significance of, and allow for tabulation of, data to identify the smaller communities in Alaska, the minimum population for CDPs outside of UAs is 25 rather than 1,000. Many CDPs correspond to the boundaries established for Alaska Native village statistical areas (ANVSAs), which represent the geographic jurisdiction of an Alaska Native village (see Chapter 5, “American Indian and Alaska Native Areas”). The population size required in UAs is the same as in the remainder of the United States, but there were no such CDPs in 1990.

CDPs in Hawaii

The Census Bureau has always noted that the population settlements in Hawaii were unincorporated. The published data before 1980, however, showed the unincorporated communities as cities, towns, or villages, and treated the places as incorporated. Beginning in 1980, all places in Hawaii were shown as CDPs. The consolidated City and County of Honolulu dates from 1907, but the Census Bureau, in agreement with local authorities (after 1960, with the Office of the Governor) treats the built-up portion of the city as a CDP (more or less coextensive with the old Honolulu judicial district) and identifies other CDPs within Honolulu County.

The minimum population for a CDP in Hawaii is 300, regardless of whether it is inside or outside of a UA. Soon after becoming a State, the Hawaii legislature enacted State Bill 1122 (Act 25 of 1963) for the purpose of establishing statistical boundaries for its cities and towns. Those entities lack the governmental powers that define incorporated places in the other 49 States, but Hawaii wanted the Census Bureau to recognize entities it defined as the equivalent of mainland incorporated places for statistical purposes. The Census Bureau corresponded with the Office of the Governor before the enactment of the legislation, and agreed to the 300 population cutoff.

CDPs in Puerto Rico

In Puerto Rico, which has no incorporated places, the Census Bureau defines two kinds of CDPs—zonas urbanas (urban zones) and comunidades (villages). Zonas urbanas, roughly equivalent to county seats in the United States, are the seats of government for the municipios, which are the statistical equivalents of U.S. counties. Comunidades, which were known as aldeas in the 1980 and earlier censuses, require a minimum of 1,000 people for recognition as CDPs; there is no minimum population requirement for zonas urbanas.

CDPs in the Outlying Areas

The population minimum for CDPs is 300 in the Outlying Areas of Guam, the Virgin Islands of the United States, Palau, and the Northern Mariana Islands; there are no CDPs in American Samoa because incorporated villages cover the entire territory and all of the population. (For details, see Chapter 7, “Puerto Rico and the Outlying Areas.”)

CDPs on American Indian reservations

Before the 1980 census, the Census Bureau had offered tribal officials the opportunity to delineate CDPs on Indian reservations. To be recognized in the data tabulations, such CDPs had to conform to the national minimum population size of 1,000. Also for 1980, tribal leaders were given the opportunity to identify small geographic areas within reservation boundaries as subreservation areas. Data users found that subreservation areas often were useful for identifying small settlements of several hundred people. For 1990, the Census Bureau discontinued the subreservation area program, but gave tribal officials the opportunity to delineate clusters of population as CDPs. To help this process, it lowered the minimum population size for CDPs on American Indian reservations from 1,000 to 250. (For further information, see Chapter 5, “American Indian and Alaska Native Areas.”)

Qualification and/or Deletion of Census Designated Places

The Census Bureau recognizes CDPs using population counts from the decennial census. The Census Bureau establishes potential CDPs before the census; these potential CDPs reflect the proposed CDPs and CDP boundaries submitted by program participants. The Census Bureau then tabulates the population of the census blocks comprising these potential CDPs. If a potential CDP meets the required minimum population size, it qualifies as a CDP and the Census Bureau includes it in its data tabulations and publications. For the 1990 census, the Census Bureau used postcensus local review counts to identify qualifying CDPs so it could include them in early decennial census data products, including the Public Law 94-171 data products. A small percentage of CDPs show a final population below the minimum size threshold because their qualification was based on the preliminary (post-census local review), rather than final counts.

The Census Bureau does not grandfather existing CDPs. CDP program participants must identify the boundaries for their proposed CDPs each time the Census Bureau implements the program. Data users may notice differences in the universe and areal extent of CDPs from one decennial census to the next for several reasons. First, all or part of the territory in a previously recognized CDP may have become part of a new or existing incorporated place. Second, the census statistical areas committees, State agencies, or tribal officials that function as program participants may have chosen not to submit a previously recognized CDP, or may have submitted previously unrecognized CDPs that qualify as new CDPs. Third, the previously delineated CDP may no longer meet one of the current criteria for qualification because of a change in criteria, or because it no longer has the required minimum population size. Finally, a previously recognized community may have been combined, renamed, or fragmented by delineation of new CDPs in such a way that the remnants of the former entity are no longer identifiable as a community.

Geographic Distribution of CDPs

State and local laws, customs, and practices greatly affect the recognition and distribution of CDPs nationwide. Several States in the Midwest region have very few CDPs because almost all population concentrations have incorporated as places. Maryland, Virginia, California, Florida, New York, and Georgia are examples of States in which a number of very large suburban population centers have developed with no legal corporate status. Strong county governments in those States provide the urban-type services that only incorporated place governments provide in many other States. In 1990, Iowa had the fewest CDPs (two), followed by Idaho (three), and Kansas and Nebraska (four each). California, Florida, and New York have the largest number of CDPs (420, 365, and 350, respectively). Table 9-7 shows the number of, and population totals for, CDPs and incorporated places in each State.

Table 9-7. Number and Population of Places, by State, in 1990

Incorporated Places Census Designated Places
(number) (population) (number) (population)
Alabama 439 2,432,988 34 165,971
Alaska 152 408,338 165 67,696
Arizona 86 2,841,026 93 271,997
Arkansas 487 1,439,864 14 49,877
California 456 23,611,378 420 3,307,677
Colorado 267 2,382,136 42 345,269
Connecticut 31 1,341,489 86 679,314
Delaware 57 193,689 15 78,000
District of Columbia 1 606,900 0 0
Florida 390 6,404,550 365 3,235,065
Georgia 535 2,582,207 64 665,738
Hawaii 0 0 125 1,044,884
Idaho 200 622,296 3 9,230
Illinois 1,279 9,627,226 29 119,071
Indiana 566 3,529,940 24 92,167
Iowa 953 2,123,410 2 4,901
Kansas 627 1,963,658 4 18,167
Kentucky 438 1,754,314 33 240,003
Louisiana 301 2,179,952 90 704,523
Maine 22 357,890 84 257,160
Maryland 155 1,412,144 174 2,428,519
Massachusetts 39 2,794,054 192 1,536,981
Michigan 534 5,453,808 86 847,662
Minnesota 854 3,440,199 9 8,325
Mississippi 295 1,295,616 29 80,466
Missouri 942 3,362,721 19 209,938
Montana 128 443,674 34 64,697
Nebraska 535 1,179,171 4 21,619
Nevada 18 654,796 38 416,809
New Hampshire 13 388,467 47 168,971
New Jersey 320 3,871,495 179 2,085,540
New Mexico 98 972,462 76 202,361
New York 619 11,536,658 350 3,026,714
North Carolina 511 3,025,500 100 353,123
North Dakota 366 449,708 10 24,018
Ohio 941 7,226,989 111 547,290
Oklahoma 592 2,387,807 6 23,349
Oregon 241 1,760,087 43 307,687
Pennsylvania 1,022 5,856,373 275 1,367,408
Rhode Island 8 534,980 19 192,589
South Carolina 270 1,275,966 72 367,375
South Dakota 310 459,994 24 31,907
Tennessee 336 2,844,151 37 145,086
Texas 1,171 12,978,796 105 551,388
Utah 228 1,319,496 27 282,436
Vermont 51 155,429 18 58,409
Virginia 229 2,630,169 116 1,394,799
Washington 266 2,433,546 160 1,285,674
West Virginia 230 671,046 47 108,060
Wisconsin 583 3,406,644 35 75,282
Wyoming 97 317,069 12 24,545
United States 19,289 152,942,266 4,146 29,595,737

Source: CPH-2 series (U.S. Summary and State reports).

Place Codes

Geographic identification codes (geocodes) are unique identifying numbers that the Census Bureau assigns to all tabulation entities for computer processing. The Census Bureau assigns another set of codes only to functioning governmental units for processing its Census of Governments. The United States Geological Survey (USGS) administers the Federal Information Processing Standard (FIPS) 55 code system for locational entities, which include places, MCDs, American Indian reservations, and communities that are not recognized by the Census Bureau as either incorporated places or CDPs. This discussion deals only with codes for places recognized by the Census Bureau.

There are three types of codes for places. The first, the census place code, is a four-digit identifier that reflects the alphabetical order of all census places (including CDPs) within a State. The Census Bureau initially assigned these codes in increments of five to permit subsequent insertion of newly incorporated places or new CDPs. The Census Bureau revises these codes if it becomes necessary to maintain the alphabetic sequence for new places. The second, the governmental unit (GU) code, is used mainly in the Census of Governments and related surveys. This code is a three-digit identifier that is unique only within county; therefore, it must be used in conjunction with the remainder of the State, county, and MCD components of the code. The result is a nine-digit identifier. As the name implies, there are no GU codes for CDPs.

The USGS assigns the third type of code, the FIPS 55 code, which is a five-digit code assigned within a State considering the alphabetical sequence of names for all places, MCDs, and other named communities and locational entities such as well-known landmarks. There is a special set of class codes to distinguish between incorporated places, CDPs, MCDs, and the other classes of named entities. FIPS codes 90000–98999 are used for CCDs and some nonfunctioning MCDs; the USGS assigns the other numbers based on the alphabetic sequence of the locational entities within the individual States. FIPS codes are being adopted as a national standard for Federal agency data presentation, and will be used exclusively, in lieu of the census MCD and place codes, before the 2000 census.

The Census Bureau also assigns additional descriptive codes associated with places. Place size codes identify the population range (for example, a population of 500 to 999) within which each entity is located. Place description codes identify central cities of metropolitan areas and central places of UAs. In 1993, the Census Bureau produced the TIGER/GICS™ (Topologically Integrated Geographic Encoding and Referencing/Geographic Identification Code Scheme), a machine-readable file that contains the names of all places along with their census and FIPS 55 (but not GU) identification codes, and descriptive codes including those that identify place size, place description, and location within a metropolitan area. Each record also contains information about the land and water area of the place, and an internal point of latitude and longitude displayed in decimal degrees rather than minutes and seconds. In addition, the 1980 GICS publication showed whether census blocks existed for the individual areas; this was not necessary for the 1990 census product because by 1990, the Census Bureau had extended census block coverage to the entire Nation.