Steve Sailer vs. Matthew Dowd

Steve Sailer discusses population trends in Mexico.

One thing I remember from this: "Population momentum" is also known, as I recall, as the "bulge in the snake" effect, because when looking at population bar graphs that plot the population at various ages like so,

0-10 XXXXXXXXXX
11-20XXXXXXXXX
21-30XXXXXXXX
31-40XXXXXXXX
41-50XXXXXXXXX
51-60XXXXXXXX
61-70XXXXXX
71-80XXXXX
81++XX

a baby boom results in a bulge in the youngest group that gradually advances through the different age groups as time passes, like a large animal, swallowed whole, moves down a snake's body.

In any case, a decrease in the birth rate doesn't begin to decrease population until the number of people who are dying overtake the number of people being born, so if we assume three to four generations at any one time, population doesn't begin to decrease until the youngest generation is smaller than the oldest, or until the grandparents and/or the great-grandparents (and others in their generation) outnumber the children.

Population momentum (also known, I think, as "demographic momentum") is, of course, a vital point to consider in any population growth model.

That is all.