pesos.[1] This is a marked gain and might indicate an encouraging general increase of commodity shipments. A detailed comparison to determine the degree to which such a development did or did not occur is not possible with the statistics at hand. It seems clear from an analysis of certain items, concerning which information is available, that the result is to be attributed more to the general high level of prices in the world's markets and the unusual circumstances surrounding certain lines of production than to a general revival of commerce in the republic. In the case of silver, which is regularly one of the most important of Mexican exports, the actual production was not unusual. The yield of Mexican silver mining from 1907 to 1914 remained practically stable at an average of about 70,000,000 troy ounces per year. The next two years saw a sharp decline, only 22,838,400 ounces being produced in 1916. Thereafter the totals rose, reaching 62,517,000 ounces in 1918 and about 75,000,000 ounces in 1919. Meanwhile, however, the value of silver per ounce had very greatly increased. It averaged $.60835 United States currency in 1912 and $.57791 in 1913 but rose to $.96772 in 1918 and to $1.11122 in 1919. Had silver remained at near its average pre-war level, therefore, or had it been at the levels it has since reached, the value of that portion of Mexican export trade would have shown a decline as compared to 1912-13.
In the case of petroleum a remarkable increase of yield has occurred, but without the cooperation or en-
- ↑ Presidential address of C. Adolfo de la Huerta, Diario Oficial, September 2, 1920, p. 25 et seq.
