U.S. Hispanic and Asian populations growing, but for different reasons (Pew Research Center, 26 June 2014)
U.S. births have been the primary driving force behind the increase in the Hispanic population since 2000 and that trend continued between 2012 and 2013. The Census Bureau estimates that natural increase (births minus deaths) accounted for 78% of the total change in the U.S. Hispanic population from 2012 to 2013.
By comparison, growth in the Asian American population has been fueled primarily by immigration. Fully 74% of Asian adults in 2012 were foreign born according to Pew Research Center analysis of Census data, and international migration accounted for about 61% of the total change in the Asian American population from 2012 to 2013. (Asian American figures represent the population who reported their race alone or in combination with one or more races, and includes Hispanics. Hispanics are of any race.)