Behind the Surprising Jump in Multiracial Americans, Several Theories

Families across the country have grown more diverse. A design change in the census form also allowed the government to report people’s identity in greater detail.

WASHINGTON — The Census Bureau released a surprising finding this week: The number of non-Hispanic Americans who identify as multiracial had jumped by 127 percent over the decade. For people who identified as Hispanic, the increase was even higher. The spike sent demographers scrambling. Was the reason simply that more multiracial babies were being born? Or that Americans were rethinking their identities? Or had a design change in this year’s census form caused the sudden, unexpected shift? The answer, it seems, is all of the above.