ABSTRACT
The greatest change in the measurement of race in the history of the United States occurred in the census of 2000. For more than two centuries, the federal statistical system had classified each respondent into a single race. The multiple-race option is a dramatic change in the federal statistical system, but there is a telling demographic analogy. Multiple-race reporting was more common among the young, reflecting the demographic consequences of increasing interracial marriage. Although a small number of studies attempted to estimate changes over time in the frequency of interracial marriages (Kalmijn 1993, 1998), few data sets lend themselves to the measurement of rare events. Until 1967, some states prohibited marriages across racial lines, and so there are few data on the mixed-race offspring of interracial unions. However, public-use files from census data may be used to ascertain the percentage of married couples in which the husband and wife reported different races.
