1. Demographic statistics (fertility rates, proportion of deaths to births, etc.), collected in developed countries or in urban environments, will not correspond to those from rural or developing environments.

2. This is because the population increases in relation to the fertility rate, which is itself dependent on the relative ease of supporting a family. If the ease is greater, more people will reproduce, and do so earlier in life.

3. In large metropolitan areas, where people outnumber job positions, a large number of people will postpone starting a family - while they have doubts about their ability to support such a family, given the higher cost-of-living associated with life in a big city - so they will remain single and employed in low-level jobs. For this reason, cities do not by themselves generate the population needed to sustain their size, and deaths outnumber births.

4. A similar trend can be observed for developed countries: all available land is occupied (built or under cultivation) and those who do not own any are forced to work for those who do. The greater the population, the larger the rate of workers to owners, and the lower the wages; therefore the greater the burden of supporting a family. While cities can absorb an influx of people from the country-side, there will be a slight incentive for reproduction in rural areas, and a corresponding growth of population there, but even that will not always be true.

5. Europe is generally fully-developed, both in towns and in the country-side, and so cannot increase its population. America is populated mainly by native hunter-gatherers, whose way of life is the least efficient, in terms of area requirements, for supporting population growth (pastoralist lifestyles are more efficient, farming even more so, and manufacturing the most efficient of all). Europeans arriving in North America found the land fully-settled, but since their requirements for their own habitations were so much smaller, they did not encroach very much on the native living space, so the natives did not mind ceding some of their land, and the settlers could supply them with many things they wanted (especially trinkets; natives love trinkets).

6. Given this abundance of land in America, and its cheapness, any laborer who has knowledge of agriculture, can in short time save enough money to purchase land, on which to start a farm, on which a family may subsist. Such people are unconcerned about the prospects of their progeny, for if they even bother to wonder about it at all, they see that land will be plentiful and cheap for as far into the future as they care to think about, all circumstances being equal.

7. Expect the population to double every 20 years.

8. Don't worry about it.

9. The end.