The U.S. population is growing at the slowest rate since the Great Depression after two decades of robust increases.
For two consecutive years since 2009, the population has grown just 0.7% a year, down from annual increases around 1% in previous years and the lowest since the late 1930s. The U.S. gained 2.2 million people from 2010 to 2011 - fewer than the 2.8 million added a decade earlier - reaching a total of 311.6 million.
"Almost anybody who observes these things over the years can say this is almost all recession-related," says Carl Haub, demographer for the Population Reference Bureau.
The government says the recession ended in June 2009. Although the economy has improved, the downturn's effect on birth and immigration lingers. The number of babies born from July 1, 2010, to July 2011 dropped 200,000 from the same period in 2008-09. The number of additional immigrants fell 150,000.
"It's an indicator of an unhealthy economy," Haub says. "People are obviously still delaying births, and immigration has continued to drop because job opportunities are not there."
The U.S. fertility rate - which has been close to the replacement level of 2.1 children per woman in contrast to many developed nations that are well below that level - now is estimated to have fallen to 1.9, says demographer Joseph Chamie, former director of the United Nations Population Division and more recently research director at the Center for Migration Studies.
Demographers expect population growth to pick up when the economy rebounds fully, but a bounce-back in births is likely to lag.
"Many - but likely not all - of the postponed births can be expected to be made up," Chamie says. "Even with the slight current downturn in births, the U.S. population will very likely reach 400 million midcentury."
For much of the nation's history, a booming population symbolized economic vitality and growing influence in the world. But environmental groups have questioned how many more people the nation can support, fueling a push for "sustainable" communities that encourage conserving green space and relying less on autos.
"Population does not necessarily equal economic growth anymore," says Bill Fulton, vice president for policies and programs at Smart Growth America, a coalition of environmentalists, planners and others working to slow sprawl.
He points to Las Vegas' population boom, which created low-paying jobs that disappeared when the housing market collapsed. By contrast, he says, cities such as Pittsburgh lost population but household wealth went up.
"We're still talking about adding a lot of people," Fulton says. "We know we can't environmentally sustain those people living in sprawled locations. ... Local governments are not going to be able to afford sprawl anymore."
By Haya El Nasser, USA TODAY