Thirteen percent of adopted children younger than 18 across the U.S. were adopted from foreign countries, and more than half were born in Asia, according to a Census report released Wednesday.

The report – the first from the Census on adoptions since 2003 – finds that 2 percent of the nation’s 64.8 million children younger than 18 were adopted. Adopted children tend to live in households with higher incomes and are less likely to live in poverty than peers who are either stepchildren or biological children, the agency says.

“There are different ways to adopt, but most of them cost some money,” says Rose Kreider, a Census family demographer and the report’s lead author. “If you’re going to adopt your stepchild, it’s a very different thing than if you adopt someone from China to whom you’re not related. Every adoption is not going to cost $30,000.”

Pediatrician Jane Aronson of New York City, who founded the Worldwide Orphans Foundation to improve the lives of orphans, says Americans have long been interested in international adoption.

“People are inclined to help children abroad who don’t have anything,” says Aronson, who wrote Carried in Our Hearts, a 2013 book about international adoption.

Compared with U.S.-born adopted children, internationally adopted children were more often Asian, and less often white, black or Hispanic.

Among other findings:

28 percent of all adopted children younger than 18 were adopted by a parent whose race or origin was different from the child’s.

37 percent of adopted children whose parents were of a different race or ethnicity were foreign-born.

Using a variety of Census data collected from 2009-2012, the report finds that of the 1.1 million households in the U.S. with adopted children, 30 percent contain members of different races, up from 18 percent in 2000.

“The increase in the adoption of foreign-born children by U.S. residents played a large role in creating these households and in the increase from 2000 to 2010,” the report says.

Of the adopted children whose race or origin is different from the adoptive parents’, more than one-third were foreign-born. Among adopted children, those whose race or origin differs from that of their parents tend to live in wealthier households than U.S. native-born adopted children.

Compared with U.S.-native adopted children, a higher percentage of children whose race or origin differs from their adoptive parents lived in households with incomes of at least $100,000.

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