US Birth Rate Up
For the first time in 30 years, American women are having enough babies to keep the population constant.
That statement comes from an article in the February 13, 2002, issue of the newspaper USA Today, citing numbers from the National Center for Health Statistics, an agency of the US government.
According to the article, the NCHS had just completed tabulating statistics for 2000. And if we take the numbers for that year and assumed they remained constant for all women for the rest of their lives, we find that the average American woman would have 2.1 children in her lifetime. This is just barely enough to replace herself and one man when they die.
The last time that American women were having enough children to keep pace with deaths was in 1971. For the past 30 years, the United States has been a course that would lead to the dwindling and eventual extinction of its population. This is true not just in percentages but in absolute numbers: 2000 was the first year since 1993 that the total number of births exceeded 4 million.
And during that same 30 years, Americans have been warned repeatedly about the "population explosion".
Statistics can be confusing, so for those interested in details, let me clear up some technicalities:
- Although American women have not been having enough children to replace themselves and a corresponding man, US population continued to rise during this period. There are two reasons for this: One is that the population is not distributed evenly over different age groups. In the 50's America had a "baby boom", lots of children born, for a variety of social reasons. In the 70's and 80's these children were having babies of their own. So even though they were having fewer babies per family than their parents had, because there were so many of them, the total number of babies born was large. In other words, there is a bulge going through the statistics.
The second reason is immigration: America's low birth rate is offset by the fact that a lot more people move to America than move away.
- Of course it is unlikely that these birth rates will remain constant for the rest of every woman's life, these things go up and down every year, so this is just a snapshot of a moment in time, what things would be like if present trends continued indefinately.
- Logically, you would think that each woman would have to have exactly 2 children in her lifetime to keep the population constant. But the way these statistics are calculated is, basically, by counting what percentage of women of any given age have a baby that year, and then adding up those percentages for all the years in a woman's life. But of course, some women die before reaching the end of their child-bearing years, and the numbers are not adjusted for this. So for the average woman to really have 2 children in her lifetime, the calculated value must be about 2.1 to 2.2 for American women. (The exact number depends on women's life expectancy.)
Posted 27 Feb 2002.
Copyright 2002 by Pregnant Pause