DALLAS — Four Texas metropolitan areas were among the biggest population gainers as Americans continued their trend of moving to the Sun Belt in 2006 and 2007, according to Census Bureau estimates released yesterday.

Dallas-Fort Worth added more than 162,000 residents between July 2006 and July 2007, more than any other metro area. Three other Texas areas — Houston, Austin, and San Antonio — also cracked the top 10.

Atlanta saw the second-largest population jump with just over 151,000 new residents. Phoenix was third with more than 132,000, and was followed by Houston, Riverside, Calif., Charlotte, N.C., Chicago, Austin, Las Vegas, and San Antonio. Of the 50 fastest-growing metro areas, 27 were in the South and 20 were in the West. Two were in the Midwest, one — Fayetteville, Ark. — straddles the South and Midwest and none was in the Northeast. Detroit lost more than three times as many people as any other metro area — its population declined more than 27,300. Other areas losing more than 5,000 people were Pittsburgh, Cleveland, Columbus, Ga., Youngstown, Ohio, and Buffalo, N.Y.

Experts credit much of the growth in the South to relatively strong local economies and housing prices that are among the most affordable in the U.S.

“People are running away from unaffordable housing, from the economic slowdown,” a state demographer in Texas, Karl Eschbach, said. “I would expect Texas to stay at the top of a slowing game.” According to figures compiled by Mr. Eschbach, 16% of Americans who moved to other states between July 2006 and July 2007 came to Texas, which led the nation for the second straight year in that category.