Included in Gregory King's many calculations made during the final decade of the seventeenth century are his estimates of the future population of England. He expected the population of the country to grow from 5.5 million in 1700, to 6.42 million by 1800, and to 7.35 million by 1900. In fact, as Figure 3.1 and Table 3.5(a) indicate, the population of England stood at 8.66 million in 1801 and 30 million in 1901. His forecast for the maximum population of the country was around 11 million people, which he did not expect to be reached until the year 3500 (in fact it was achieved by 1820). King's projections were so wide of the mark because he thought the country had insufficient land to support more people. His assumption was that, with a finite area of land and an agricultural technology that was virtually static, anything other than a very gradual growth in population was impossible. This assumption was based on a lesson from history. Before the mid-eighteenth century English population seemed to have a natural ceiling of around 5.5 million people. Whenever population grew (during the Roman occupation, in the thirteenth century, and again in the sixteenth century) agriculture had the greatest difficulty in meeting the increased demand for food. In each case there appears to have been a check: the rise in population was halted because the increase in agricultural output was insufficient to sustain the rise in population.