7 Ways the U.S. Population is Changing

Immigration, Hispanics, and new childbearing trends are shifting U.S. demographics.


A shaky Social Security system, the DREAM Act, and a 2012 electoral map that may favor Republicans—these three political hot topics are directly linked to a U.S. population that is aging, growing from immigration, and migrating westward and southward, according to the latest. data from the Census Bureau and other entities.

[See a slide show illustrating 7 ways the U.S. population is changing.]

1. (Slowing) Growth

The most obvious and constant change to the U.S. population is growth. But 2010 census numbers show that population growth had dropped to 9.7 percent, its lowest level since the Great Depression. The U.S. growth rate has also lagged behind world population growth over the last decade. The 2010 census put the population at 308,745,538, up from 281,421,906 in 2000. The estimated world population of nearly 6.9 billion, meanwhile, is up 12.5 percent from 2000. However, U.S. growth remains ahead of many other developed nations, particularly European countries, whose populations may actually decline between now and 2050. [Check out political cartoons about immigration.]

2. Moving West and South

U.S. population growth shows marked regional differences. While the West and South saw growth rates of 13.8 and 14.3 percent, respectively, over the last decade, the Midwest grew only by 3.9 percent, and the Northeast by a mere 3.2 percent. These figures reflect a movement of young people westward, as well as an immigrant population settling heavily in the south and west. According to the Pew Hispanic Center, the state with the largest share of foreign-born residents is California, with 26.9 percent. Another western state, Montana, posted the largest increase of foreign-born people over the last decade, with a 60.9 percent jump. The mean center of U.S. population has moved steadily westward and slightly southward since the first census, in 1790. Since that time, it has slowly shifted from Kent County, Maryland, to Plato, a town in southern Missouri. [See the 10 metropolitan areas with the highest population growth.]

3. Aging

The estimated population median age in 2009 was 36.8, up from 35.3 in 2000—a natural consequence of 77 million baby boomers pulling that figure upward with every passing year. The birth rate has also been relatively flat since the 1970s, and in 2009 posted the largest two-year drop in over 30 years, according to the Centers for Disease Control. Altogether, the elderly segment of the population is expected to increase dramatically. A Congressional Research Service report released this year projected that people 65 and older—currently constituting 13 percent of the population—would make up 20.2 percent of the U.S. population by 2050.

4. Becoming More Diverse (...and particularly, more Hispanic)

The white, non-Hispanic segment of the population is steadily shrinking, and has dropped from 69.1 percent in 2000 to 63.7 percent in 2010. The Census Bureau predicts that, by 2050, white people will only make up 46.3 percent of the population. The burgeoning Hispanic population is one major reason for this projected shift—the Hispanic populace grew a staggering 43.1 percent from 2000 into 2010, and is expected to make up 30 percent of the population in 2050, up from its current share of 16 percent. Other groups expected to post significant growth are Asians, from 4.7 percent in 2010 to 7.8 percent in 2050, and people of two or more races, from 1.9 percent in 2010 to 3.7 percent in 2050. [See a slide show showing the 11 cities with most Hispanics.]

5. Increasing Income Inequality

Income inequality in the United States has increased more or less steadily. As of 2009, the top 20 percent of households in the U.S. earned 50.3 percent of all household income, according to the Census Bureau. That figure is trending upward, from 49.7 percent in 2000 and 46.6 percent in 1990. In that same time frame, all other quintiles' shares of household income have dropped. The bottom 20 percent of all U.S. households in 2009 earned 3.3 percent of all wealth. One measure of inequality is the Gini index, which measures a population's income distribution on a scale of zero (total equality) to 1 (total inequality). That, too, has risen, according to the Census Bureau—in 2000, the U.S. Gini index was 0.46, up from 0.45 in 1995. As of 2009, the Gini was up even further, at an estimated 0.469. [See the 13 cities with the least economic equality.]