Has the population scale of the United States reached the minority tipping point? The National Center for Health Statistics and the U.S. Census Bureau differ in their assessments, so the nation remains unsure whether the birth rate of minorities has finally surpassed the birth rate of whites in America.

In 2012, the Census Bureau said more than 50.4 percent of U.S. babies were part of an ethnic minority; the bureau explained that "minority" means those who classify as non-Hispanic white. It also suggested that within three decades the U.S. will be a majority-minority nation, where more than 50 percent of all Americans would be non-white. However, the NCHS says the tipping point has yet to arrive, claiming that non-Hispanic white mothers still account for 54 percent of births, in spite of a drop in those births over the last several decades. White parents claim a smaller share of newborn children each year, a fact verified by both agencies.

Members of minority groups are younger and more likely to be of child-bearing age; Hispanic and black women, on average, have more children than Asian-American women and white women. Those facts remain true, but discrepancies arise when classifying the children.

BIRTH CERTIFICATE DATA

The Census Bureau classifies children based on the race and Hispanic origin of both parents, but the NCHS exclusively reports the mother's race. The two agencies use different methods when categorizing race. Both agencies' numbers are based on information from birth certificates from each state and Washington, D.C. The challenge of an accurate classification of children lies in the fact that the certificates hold limited information about the parent's race or Hispanic origin. Some certificates only include details about the mother, particularly for unmarried mothers. Some states don't use the same racial and ethnic categories on birth certificates. And, in the past, some states have opted to simply mark "Remainder of World," rather than identifying the nationality of a parent.

"RACE-BRIDGING"

Alabama, Arizona, Arkansas, Connecticut, New Jersey and West Virginia accounted for about 9 percent of U.S. births in 2013, and those six states don't allow parents to check more than one race box for parents to describe themselves. While the mixed-raced American population is relatively small (9 million people out of 308.7 million, according to the 2010 census), that demographic is disproportionately young and rapidly growing all over the nation.

The Census Bureau drafted the "race-bridging" protocol, where people of multiple races are assigned a single race using a "probability-based model derived from research into which category they would have chosen if they were permitted to choose only one race," according to Pew Research. When multiple-race people were asked to reclassify in 2000, 53 percent changed their selection to white, 24 percent to black, 15 percent to Asian or Pacific Islander and 9 percent American Indian or Alaska Native; completely doing away with reporting on mixed-raced mothers.

REVERSE "RACE-BRIDGING" & BIRTH DATA LAG

The Census Bureau reverses the "race-bridging" when they receive birth certificate data, reclassifying some single-race people into mixed-race if they live in a state that does not allow multiple races to be documented on birth certificates. The birth certificate data happens to be the main ingredient used by the Census Bureau. This faulty system converts some non-Hispanic whites to people of mixed race, adding to the count of minorities.

The Census Bureau makes these adjustments because they have to make early estimations and projections regarding age, sex, race, Hispanic origin, state, and distribution of foreign-born immigrants, due to yearlong delays when calculating population estimates. That fact is evident when seeing that July 2012's estimate, which was released in June 2013, only included birth data up to Jan. 1, 2011. In 2010, the bureau undertook a complex, multi-stage update process, which involved population patterns and racial identification by families; nonetheless, the "when" of the current or eventual minority tipping point remains a mystery.