America is enjoying it's biggest boom in fertility in 26 years.

USA Today reports that the US fertility rate hit 2.1 in 2006, according to preliminary estimates released by the National Center for Health Statistics. It;s the first time since shortly after the baby boom ended that the nation has reached the rate of births needed for a generation to replace itself, an average 2.1 per woman. A replacement fertility rate means that there will be enough people in the future to fill jobs and to support the elderly.

Fertility levels went up in every age group from 2005 to 2006. The highest increase was among the 20 to 24 year-old age group. The US population topped 300 million last year, and the Census Bureau projects growth to 400 million by around 2040.