Based on the definitions created by the Office of Management and Budget and the U.S. Census Bureau, the concepts of race and ethnicity are mutually independent. For the Census Bureau, "ethnicity" distinguishes between those who report ancestral origins in Spain or Latin America (Hispanic and Latino Americans), and those who do not (non-Hispanic Americans). "Mexican" was officially added as a racial category on the United States Census beginning in 1930 in connection with the growing Mexican population, but was removed in the following decades due to much of the Mexican population being repatriated back to Mexico, in addition to political pressure. Prior to this, Latinos in the United States were often classified as "Mulattoes", "Indians" or, "Other" if they were not purely of European ancestry. Classification was up to each census official's discretion before the establishment of a centralized Census Bureau in 1902. A designation for Hispanic and Latino citizens returned in 1970, again coinciding with an increase of immigration from Latin America. As had been the case historically, classification of Latinos presented difficulties in the United States, for the country did not have large mixed-race domestic populations. "Hispanic/Latino" will remain as an ethnicity. Many employers had already given "Hispanic or Latino" the same demographic weight as a racial group for some time. The U.S. Census Bureau asks each resident to report the "race or races with which they most closely identify."