WASHINGTON - The United States is becoming increasingly diverse even as its overall population growth slows, with a large spike in multiracial Americans in particular, according to US census data released last week.
The number of multiracial Americans - those who identified as being of two or more races - rose from nine million people in 2010, or 2.9 per cent of the population, to 33.8 million people last year, or 10.2 per cent of the population.
The number of multiracial Americans grew in almost every county across the US over the decade, but especially in Texas and Florida.
America's non-white Hispanic and Asian populations also grew sharply. Its white population declined overall for the first time, although the share of white people as a proportion of the population has been decreasing since the 1960s.
The spike in the multiracial population is partly due to sheer demographic change, say sociologists and demographers: As interracial marriages become more common, more multiracial babies are born.
But more Americans are also identifying as multiracial - a change made possible as the census questionnaire now allows people to describe their racial background in greater detail.
Dartmouth College senior lecturer Melissa Herman, who studies multiracial youth and attitudes towards multiracial people, told The Straits Times: "The increase reflects actual changes due to both immigration and births. It also reflects the updated questionnaire design and the way the data are coded."
Beginning in 2000, Americans were given the option of choosing more than one race on the census.
The 2020 census form also differed from the 2010 edition, allowing people who ticked white and black to elaborate on their origins.
White Americans for example, could write that they were German or English, while black Americans could specify whether they were Haitian or Nigerian, for instance.
In total, the census allowed for 57 possible combinations of races for those identifying as multiracial.
In a press release, the US Census Bureau said that the observed changes in the multiracial population could be attributed to a number of factors, including demographic change since 2010.
"But we expect they were largely due to the improvements to the design of the two separate questions for race and ethnicity, data processing and coding, which enabled a more thorough and accurate depiction of how people prefer to self-identify," the bureau added.
Dr Herman said that Americans, especially white Americans, have become more accepting of interracial relationships and more aware of multiracial people in society, a gradual change since the 1990s.
She added: "Multiracial people now feel more comfortable claiming multiple groups because social norms about ethnic pride have changed. People want to celebrate all of their identities and don't want to have to reject parts of their ancestry."