Indian Americans or Indo-Americans are Americans whose ancestry belongs to any of the many ethnic groups of the Republic of India. Indian Americans comprise a subgroup of South Asian Americans, which is a further subgroup of Asian Americans. The United States Census Bureau uses the term Asian Indian to avoid confusion with the indigenous peoples of the Americas historically referred to as American Indians (or Native Americans; Indigenous Americans). With a median income of $101,591, Indian Americans are the richest and most successful ethnic group in USA.