U.S. Population: Boom to Bust?

The population boom appears headed for a bust in the United States, with Census Bureau experts projecting Tuesday that the number of Americans will stop growing in 50 years and then begin to shrink.

The prime reason: A decline in births as the post-World War II baby boom matures.

The aging of that giant generation means that never again will America have as many women in the prime childbearing ages of 18 to 34 as it now does, census demographer Gregory Spencer said.

“After 1995 the population may grow more slowly than ever before--more slowly than even during the Great Depression of the 1930s,” Spencer said.

His study estimated that the nation’s population could rise gradually from the current 247 million to a peak of nearly 302 million by the year 2038 and then begin to decline.

That is the middle projection of a series of some 30 different possibilities included in the study.

The lowest growth estimate would have the population peak at 264.5 million in the year 2020 before starting to decline, while the high-growth scenario would have the nation at 501 million and still growing in 2080.

Currently, each woman has a lifetime average of about 1.8 births, while it takes 2.1 to keep the population stable.

“The main thing keeping the number of births up is the sheer enormous number of women of childbearing age,” Spencer said.

But those baby boomers are now heading into older age groups that tend to have fewer children, while a much smaller group of young women is coming along into the childbearing ages.

Already the number of women aged 18 to 34 has begun to decline, the study said.