ancestries that were not black. The comparable figures were 8 percent for Asians and 9 percent for Hispanics.

Fertility Assumptions

Fertility is the starting point of any demographic projection model. Higher fertility rates will make the future population larger, and subgroups with higher than average fertility will grow relative to others.

Since 1971, the Census Bureau has published fertility estimates in a special supplement to the Current Population Survey (CPS) in June of each year. The survey asks women several fertility questions, including how many children they have ever borne and whether they have had a child within the past year. Starting in 1994, the CPS has also asked about the nativity of the respondent and the parents of the respondent. Using the CPS nativity data, we tabulated the population for the foreign-born (first generation), sons and daughters of the foreign-born (second generation), and native-born of native-born parents (third and later generations).9

There is apparently some underreporting of births in the CPS, when compared with vital statistics for registered number of births. Births are registered for a calendar year, whereas CPS data on reported births are from July of the preceding year to June of the survey year. We tabulated the number of births from vital statistics and the CPS by race/ethnicity, along with the adjustment factors to scale CPS data to the known level of births by race of mother.10

Age-specific fertility rates for the four major racial/ethnic groups were estimated using recent fertility data from the June 1994 CPS and the tabulations for 1994 of the National Center for Health Statistics (NCHS). Separate estimates were made for the first, second, and third and later immigrant generations (fertility levels for the third and fourth and later generations were assumed to be the same). Overall, the following total fertility rates were assumed for the starting period of 1995 to 2000:1.81 for the white population, 2.33 for Asians, 2.34 for blacks, and 2.63 for Hispanics. As the generational composition shifts, the pro-


The CPS has two important limitations for fertility estimates: undercoverage of the population and underreporting of births. The first results from omitted households and from missing persons within sample households. Although the CPS has lower rates of undercoverage than do other large federal household surveys, its undercoverage is about 8 percent lower than that of the 1990 census (Shapiro et al., 1993). Undercoverage rates vary with age, sex, and race. For some groups, such as black males aged 20 to 29, the rate is estimated to be as high as 34 percent compared with that of the 1990 census. Although the CPS is adjusted for undercoverage, the extent to which the weighting procedure corrects for fertility reporting bias due to undercoverage is unknown.


Fertility estimates derived from the CPS are subject to sampling variability. To provide a range of the variability, we calculated standard errors for some of the fertility estimates. For the native-born white population, we calculated that the total fertility estimate of 1.81 has a standard error of ± 0.04.

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