The bureau's latest race and ethnicity breakdowns once again showed the increasing diversity of the U.S. populace, mirroring the explosive growth among minority groups detected in the previous decade by the 2000 head count.
Hispanics, the nation's largest minority, numbered 39.9 million in July 2003, up 13 percent from April 2000, according to the figures released Monday. The U.S. population overall grew 3 percent during that time to 290.8 million.
Asians were the next fastest-growing minority group, up 12.6 percent to at least 11.9 million, while the black population rose nearly 4 percent to at least 37 million.
Immigration fueled the surge of the Hispanic and Asian populations over the 1990s, and the latest data appears to show that it did not subside at the start of this decade in spite of the recession and the effects of the Sept. 11, 2001 terrorist attacks, said John Logan, a sociologist at the State University of New York at Albany.
Another factor in Hispanic growth is that Latinos have a higher birth rate than other population groups.
Whites remain the single largest group at 197 million, up just 1 percent between 2000 and 2003. That number refers to those U.S. residents who are not of Hispanic ethnicity and who selected only white as their race.
Nearly 7 out of 10 U.S. residents are white.
The Census Bureau counts "Hispanic" or "Latino" as an ethnicity rather than a race, so Hispanics can be of any race, including white.
"Non-Hispanic white" is what would generally be considered the majority group in the U.S. population, though they are not officially designated as such.
Bureau projections released earlier this year showed that whites and minority groups overall would be roughly equal in size by 2050.