Washington, Jun 22 (IANS): The American population is growing older and more diverse than ever before, a new census report has revealed.

The nation's median age is 37.9 years old, more than two years more than the median age in 2000, according to the new Census Bureau report released on Wednesday night.

The number of Americans over 65 years old has jumped from 35 million at the turn of the century to 49.2 million, reports The Hill magazine.

Whites continue to be the biggest racial group in America, accounting for 256 million people in 2016.

But their population grew by only 0.5 per cent, fuelled largely by immigration; non-Hispanic whites experienced a natural decrease of 163,000, meaning more whites died than were born last year.

The Asian American population grew by 3 per cent, to 21.4 million last year. The African American population jumped 1.2 per cent, to 46.8 million, and the Hispanic population expanded by 2 percent, to 57.5 million.

That graying of America comes as the Baby Boom generation born between 1946 and 1964 edges toward retirement, according to the report.

At the same time, younger Americans are going through what some demographers call a baby bust, either choosing not to have children or delaying the decision to get pregnant.

The number of annual births has fallen steadily since 2007, when it hit a record high of 4.3 million, according to Cheryl Russell, a demographer and editor in chief of New Strategist Press.

In 2015, 3,978,000 babies were born, the National Centre for Health Statistics reported, ten thousand fewer than the year before.

Pennsylvania is one of seven states that lost population between 2015 and 2016, the Census Bureau reported.

Illinois lost more residents than any other state (37,500) while Connecticut, Mississippi, New York, Vermont, West Virginia and Wyoming all bled population, The Hill magazine quoted the report as saging.

Texas led the nation in population growth, adding nearly 433,000 new residents in the past year.

Florida added 367,000 residents, while California tacked on more than a quarter million. Last year, Florida surpassed New York to become the nation's third-largest state.