The United States is becoming a far more diverse nation, led by surging growth among those of Asian and Hispanic descent, while stagnating fertility rates slow overall population growth.
A new report from the U.S. Census Bureau shows America's population is 60.1 percent white, the lowest level ever recorded. Among those under 16 years of age, fewer than half are white, a sign that white Americans are having fewer children and doing so later in life.
"The nation is becoming more diverse, especially among the young," said William Frey, a demographer at the Brookings Institution.
But the number of Americans under the age of 25 actually fell over the last decade, driven entirely by lower fertility rates among whites. There are 4.7 million fewer white Americans under the age of 25 today than there were in 2010, and 3.1 million more minorities under the age of 25 than there were nine years ago — an overall decline of almost 1.6 million.
The only age group in which whites are growing as a share of the population is among seniors as the baby boom generation ages into retirement.
The number of senior citizens in America, those over the age of 65, has grown by more than a third since 2010, the Census Bureau said. The median age of an American has grown by more than a full year, to 38.4 years old, over the last decade as people live longer and have fewer children.
"The first Baby Boomers reached 65 years old in 2011," said Luke Rogers, chief of the Census Bureau's Population Estimates Branch. "Since then, there’s been a rapid increase in the size of the 65-and-older population."
Since 2016, all but three metropolitan areas in the country have gotten older, according to an analysis by Indeed, the job-search platform. Those three metropolitan areas where the median age fell were Harrisburg and Scranton, Pa., and Lakeland, Fla., already one of the oldest metro areas in the nation.
Asian Americans represented the fastest-growing segment of the population over the last decade. The number of Asian Americans in the United States grew to 22.8 million, a 29 percent increase.
The number of people of Hispanic descent grew by 10 million, or 20 percent over the last decade. The median age among Hispanics is 29.8, though that number has risen two years over the last decade, a sign that fertility rates are slowing across racial and ethnic lines.
Bi- and multiracial Americans are the youngest cohort, with a median age of just 21 years old.
Today, Hispanics make up 18.5 percent of the population, according to Frey's analysis, and 25.8 percent among those under the age of 16. African Americans make up 12.5 percent of the population as a whole, and 17.7 percent of those under 16. Whites make up just a shade under 50 percent of the under-16 population, the first time in American history they have dropped below majority status among the youngest cohort.
But growth rates are slowing across racial groups, a sign that what demographers call the baby bust extends nationwide. The Centers for Disease Control and Prevention said in May that the national birthrate has hit its lowest level in two generations. Only 3.7 million children were born in 2018, the lowest total number of births since 1985.
Indeed's analysis found that Western cities are far more likely to have diverse populations. The most diverse metropolitan areas in the country are San Jose, Houston and San Francisco, the only three cities in the country where the largest racial or ethnic group represents less than 40 percent of the population.
Among the ten most diverse metro areas in the nation, only one — Washington, D.C. — is east of the Mississippi River.