Japanese Americans are Americans of Japanese ancestry. Japanese Americans were among the three largest Asian American ethnic communities during the 20th century; but, according to the 2000 census, they have declined in ranking to constitute the sixth largest Asian American group at around 1,469,637, including those of partial ancestry. The United States has the second largest Japanese population outside of Japan, second to only Brazil. However, in terms of Japanese citizens, the United States has the most Japanese-born citizens outside Japan, due to Brazil's Japanese population being multigenerational.