The first batch of 2010 census race and migration data comes out Thursday, and it’s expected to show that racial and ethnic minorities accounted for 90 percent of population growth since 2000. The Hispanic population is on track to exceed 50 million people, or about one in six Americans, and for the first time Asians had a greater numeric gain than African Americans, still the second-largest minority group at 37 million. As people moved South and toward the Sun Belt, the population center of the country left the Midwest for the first time since 1850, landing on Plato, Missouri. "This really is a transformational decade for the nation," said William H. Frey, a demographer at Brookings. "The 2010 census shows vividly how these new minorities are both leading growth in the nation's most dynamic regions and stemming decline in others."