First, birth rates are dropping, which means that fewer and fewer people will be paying into Social Security and Medicare as more and more people are drawing benefits from them.
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.2 The overall U.S. birth rate peaked most recently in the Baby Boom years, reaching 122.7 in 1957, nearly double today’s rate. The birth rate sagged through the mid-1970s but stabilized at 65-70 births per 1,000 women for most years after that before falling again after 2007, the beginning of the Great Recession.
In addition to the birth rate decline, the number of U.S. births, which had been rising since 2002, fell abruptly after 2007—a decrease also led by immigrant women. From 2007 to 2010, the overall number of births declined 7%, pulled down by a 13% drop in births to immigrants and a relatively modest 5% decline in births to U.S.-born women.Second, immigrants and their children will make up an increasing share of the population.
Despite the recent decline, foreign-born mothers continue to give birth to a disproportionate share of the nation’s newborns, as they have for at least the past two decades. The 23% share of all births to foreign-born mothers in 2010 was higher than the 13% immigrant share of the U.S. population, and higher than the 17% share of women ages 15-44 who are immigrants. The 2010 birth rate for foreign-born women (87.8) was nearly 50% higher than the rate for U.S.-born women (58.9).
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Population projections from the Pew Research Center indicate that immigrants will continue to play a large role in U.S. population growth. The projections indicate that immigrants arriving since 2005 and their descendants will account for fully 82% of U.S. population growth by 2050.8 Even if the lower immigration influx of recent years continues, new immigrants and their descendants are still projected to account for most of the nation’s population increase by mid-century.
