Although the NMFR for black women was consistently higher than those for katinas and white women, the demographic sources of racial or ethnic differences in NMFRs may not be uniform and may have changed over time.
In 1994, blacks' NMFR was 50 percentage points higher than whites'; most of this difference resulted from the much higher black nonmarital fertility rate (25 percentage points) and lower marriage rate (20 points).
At the beginning of the study period, a high rate of marriage among foreign-born teenagers in 1994 clearly placed downward demographic pressure on their NMFR and narrowed the difference between the groups' ratios, and a higher nonmarital fertility rate among native-born Latinas had the opposite effect.
Observed nonmarital fertility ratios for women aged 15-44, 1994 and 2005; ratios standardized for selected demographic components; and change in ratios over time--all by women's rate or ethnicity Observed Standardized NMFR NMFR Race/ Age Proportion ethnicity distribution of women married Latina 2005 47.
Unfortunately, our understanding of the demographic foundation of recent trends and differentials in NMFRs among Latinas is limited.
Obviously, NMFRs can change over time if fertility rates among unmarried women change.
Among Latinas, high NMFRs coexist with familial and cultural norms that support traditional marriage, early childbearing, large families, and strong family ties and intergenerational support.
10,21) To decompose NMFRs for a population in any given year, we followed exactly the procedures described by Smith and colleagues.
The modest changes in NMFRs between 1994 and 2005, however, do not eliminate the possibility (even likelihood) that the mix of underlying demographic components has shifted over time or differs by racial or ethnic group.
The observed NMFRs were roughly seven percentage points higher among native-born than among foreign-born Latinas over the 1994-2005 period (Figure 2).
For example, NMFRs were much higher among katinas than among whites in both 1994 and 2005 (21- and 18-percentage-point differences, respectively).
NMFRs changed very little between 1994 and 2002, before increasing in recent years.