From the handful of settlers who barely survived the first few years at Jamestown, the number of inhabitants in the thirteen colonies had grown to an estimated 2.5 million on the eve of the American Revolution. Beginning about 1660, a high domestic birth rate and a rising number of immigrants had combined to increase the population by approximately one-third every ten years. Nor did the Revolution disturb this trend. In 1790, at the time the first census was taken under the new government, the total number of people was reported at slightly in excess of 3.9 million. By this date there was a continuous line of settlements, between the mountains and the sea, extending from Maine to the northern boundary of Florida; and pioneers had already pushed their way across the Alleghanies and established themselves in Tennessee and Kentucky. (Donald Schaefer, Thomas Weiss, 1994)
This growth and spread of population is a good index of a rapidly expanding economy. Unfortunately, however, it is not possible to give any very specific information about how well the economy operated during this period. It is doubtful if anyone has even ventured a guess at the rate of growth of "national" income, but, on the not unreasonable assumption that average per capita income was no smaller during the late 18th century than it had been during the 17th, it may be concluded that the expansion in total income was at least proportional to the increase in population. Actually it was probably greater. The increase in population itself and a slowly growing supply of capital made it possible to secure the advantages of greater specialization and division of labor, at least on a limited scale. Nor, as has been pointed out in the preceding chapters, was the period without important improvements in knowledge and techniques...........
