The nation’s demographics are on a clear trajectory: White people are dying faster than they are being born, which means they are on target to become a minority in the United States in 30 years.

For the third year in a row, deaths of non-Hispanic whites outnumbered births, according to detailed population estimates for states and counties released Thursday by the U.S. Census Bureau.

“This is without historical precedent,” said Kenneth Johnson, the senior demographer at the University of New Hampshire’s Carsey School of Public Policy. “The minority population is growing, and the non-Hispanic white population is not.”

Whites currently account for 62 percent of the population but 78 percent of deaths, according to Johnson’s analysis.

Their median age — half are older and half younger — has hit an all-time high of 43, said William Frey, a demographer at the Brookings Institution. For the first time, whites are in the minority among children under the age of 5.

“Since 2010, the overall under age 20 population is declining, while working ages and especially seniors are growing,” Frey said.

White populations under 20 declined in 46 states — in all but Hawaii, Utah, South Dakota, North Dakota and the District of Columbia.

Non-Hispanic whites were the only group with a higher death rate than birthrate. As a result, their numbers grew the slowest: up 0.5 percent from 2013 to 2014, compared with 2.1 percent for Hispanics, 1.3 percent for black people, 3.2 percent for Asians, 1.4 percent for American Indians and Alaska Natives, and 2.3 percent for native Hawaiians and other Pacific Islanders.

“I don’t think people fully appreciate how much natural increase [more births than deaths] contributes to the nation’s growing diversity,” Johnson said. “If you ask people why is America more diverse, they would say it’s because minorities are being born. What nobody ever thinks about is that a lot more whites are dying.”

Minority population gains accounted for 95 percent of the U.S. population increase, largely due to Hispanic and Asian immigration, and more births.

The July 1, 2014 estimates show that the millennial generation, those people born from 1982 to 2000, is the largest group in the U.S. totaling 83.1 million — one-quarter of the population. They outnumber the previously dominant baby boomer generation by almost 8 million.

Millennials are more diverse than any previous generation. More than 44 percent are part of a minority race or ethnicity.

Five jurisdictions are already majority-minority. Hawaii has the largest majority-minority at 77 percent, followed by the District of Columbia (64.2 percent), California (61.5 percent), New Mexico (61.1 percent) and Texas (56.5 percent) Nevada, now at 48.5 percent minority, is the next expected to cross the majority-minority threshold.

California — the nation’s most populous state with 38.8 million residents — and Los Angeles County had the largest white, Hispanic, Asian and American Indian populations of any state or county. Texas added the most whites, blacks and Hispanics from 2013 to 2014.

New York had the largest African-American population 3.8 million, but the District of Columbia had the highest percentage of black residents, with 50.6 percent.

“So we are having an older white population, with whites, once again, showing a minority of births,” Frey said. “These new estimates — showing declining white births, minority white toddlers and pervasive losses in the nation’s under age 20 white population — indicate that future generations almost everywhere will be increasingly made up of minorities.”