1820 - 9,638,131 - 36.45
1830 - 12,866,020 - 33.49
1840 - 17,069,453 - 32.67
1850 - 23,191,876 - 35.87
1860 - 31,443,790 - 35.58
This shows an average decennial increase of 34.60 per cent in population through the seventy years from our first to our last census yet taken. It is seen that the ratio of increase at no one of these seven periods is either 2 per cent below or 2 per cent above the average, thus showing how inflexible, and consequently how reliable, the law of increase in our case is. Assuming that it will continue, it gives the following results:
Year - Population
1870 - 42,323,341
1880 - 56,967,216
1890 - 76,677,872