White children are now in the minority among people under 18 in 10 U.S. states and 35 large metro areas, according to a Brookings analysis of 2010 Census data.

The number of white children in metro areas including Atlanta, Georgia; Dallas, Texas; Orlando, Florida; and Phoenix, Arizona, fell below that of other children in the last decade as the population of white children nationwide declined by 4.3 million, the report said.

The decline occurred as the number of children identified as "new minorities" - Hispanics, Asians and other racial groups apart from whites, blacks and American Indians - grew by 5.5 million, the report said.

Hispanics registered an increase of 4.8 million, which kept the nation's overall child population from declining, the report said. The findings reflect changes in the racial makeup of the overall U.S. population with Hispanics becoming the nation's largest and fastest growing minority group.

Hispanics now comprise 23% of children, up from 12% in 1990, while whites now comprise just 53% of youth, down from nearly 70% in 1990.

The findings also underscore projections that the country will become "white minority" by 2042 as the race's median age keeps increasing. The child population stands to hit that mark in 2023.

"Slower growth among whites owes in part to their lower fertility rate - about 1.9 births per white woman, compared with 3.0 births per Hispanic woman - as well as a relatively low contribution to population growth from immigration" the report stated.

From 2000 to 2009, only 15% of growth in the immigrant population was attributable to whites, compared with 78% for Hispanics, Asians and other new minorities.

The report also said the aging white population contributes to a lower growth rate because proportionately, fewer white women are in their child-bearing years.

"The median age of whites is 41, compared to 27 for Hispanics, 35 for Asians, and a staggering 20 for the population of more than one race. As a further reflection of these age differences by race and ethnicity, just one-fifth of U.S. whites are under age 18, compared with one-third of all Hispanics."

The study also found that the decline in white children reduced the growth rate of the overall child population, from 13.7% in the 1990s to 2.6% in the 2000s. Though variation from state to state in child growth was considerable, on the whole, 46 states registered declines in their white child populations.

Not surprisingly, most of the states that experienced growth in populations of minority children are the ones where white children are in the minority: California, Nevada, New Mexico, Arizona, Texas, Florida, Georgia, Hawaii, Mississippi and Maryland.