Bloomberg gets birth headline wrong

In an article published yesterday, and based off of birth rate trends reported by the Pew Research Center, Bloomberg Businessweek reported that U.S. births are at their lowest since 1920.

Source: Bloomberg Businessweek

Not so fast...

The Pew analysis, based on National Vital Events records and American Community Survey data, found that the birth rate is at its lowest point on record in the United States. Pew's authors write:

The overall U.S. birth rate, which is the annual number of births per 1,000 women in the prime childbearing ages of 15 to 44, declined 8% from 2007 to 2010. The birth rate for U.S.-born women decreased 6% during these years, but the birth rate for foreign-born women plunged 14%—more than it had declined over the entire 1990-2007 period.1 The birth rate for Mexican immigrant women fell even more, by 23%.

Final 2011 data are not available, but according to preliminary data from the National Center for Health Statistics, the overall birth rate in 2011 was 63.2 per 1,000 women of childbearing age. That rate is the lowest since at least 1920, the earliest year for which there are reliable numbers.

The 2011 birth rate, indeed, appears to be the lowest on record. However, the U.S. population is three times larger in 2011 than it was in 1920 (105.7 million in 1920 compared with 311.0 million on April 1, 2011).

As a result of the two combined demographic forces, a growing population and a declining birth rate, the total number of births is still higher in 2011 (3,953,600) than it was in 1920 (2,777,000).

The chart, from CDC, illustrates this point. The darker blue line represents the total number of births, while the lighter colored line represents the rate.

Source: CDC

Births and the birth rate are not one and the same.

This might seem like an unimportant nuance, but consider the implications for school planning if the public is led to believe that five years from now there will be fewer children in Kindergarten than there were during World War I...