NCHStats

Questions for Brady E. Hamilton, Ph.D., Demographer, Statistician, and Lead Author of “Total Fertility Rates by State and Race and Hispanic Origin: United States, 2017”

Q: Why did you decide to do a report on the total fertility rate in the United States?

BH: We produced this report because we were interested in what differences there were in the total fertility rate (TFR) by state and population group (race and Hispanic origin). This report presents the TFR for each state in 2017, both overall and for the three largest population groups — non-Hispanic white, non-Hispanic black, and Hispanic. As noted in the report, fertility levels affect the size and composition of the population, and family size is associated with female labor force participation and economic growth, as well as other social and economic changes.

Q: Can you explain what the total fertility rate is and how is it different from the general fertility rate and crude birth rate?

BH: The total fertility rate is the number of births expected for a (hypothetical) group of 1,000 women over their lifetime, assuming the current age-specific birth rate hold. The crude birth rate and general fertility rate measure the number of births occurring for either the whole population or the population of women in their childbearing years (ages 15-44 year) in a given year. The TFR, on the other hand, estimates the number of births for women over a generation. For that reason, the TFR can be used to ascertain whether the number of births is at “replacement,” that is, the level at which a given group of women can exactly replace themselves (generally considered to be 2,100 births per 1,000 women for the TFR).

Q: How did total fertility rates vary by state and race in 2017?

BH: Differences in the total fertility rates among the states by race and Hispanic origin were considerable. For non-Hispanic white women, the TFR for Utah (2,099.5, the highest) was more than double the TFR for the District of Columbia (1,012.0, the lowest). For non-Hispanic black women, the TFR for Maine (4,003.5) was 3.5 times higher than that for Wyoming (1,146.0). For Hispanic women, the TFR for Alabama (3,085.0) was 2.6 times higher than the TFR for Vermont (1,200.5). In addition, there were no states with TFRs above replacement for non-Hispanic white women in 2017. However, for non-Hispanic black women, the TFRs for 12 states was above replacement. The TFRs for Hispanic women were above replacement in 29 states.

Q: Do you have trend data on total fertility rates that goes back 10 or 20 years?

BH: The report includes only data for 2017. However, trend data for the total fertility rate at the national level, by race and Hispanic origin group, are available from Births: Final Data for 2017 (https://www.cdc.gov/nchs/data/nvsr/nvsr67/nvsr67_08-508.pdf), Births: Final Data for 2015 (https://www.cdc.gov/nchs/data/nvsr/nvsr66/nvsr66_01.pdf), and Trends and Variations in Reproduction and Intrinsic Rates: United States, 1990-2014 (https://www.cdc.gov/nchs/data/nvsr/nvsr66/nvsr66_02.pdf). In general, the TFR has declined over the last six decades, with the TFR being below replacement for all but two years (2006 and 2007) since 1971. In 2017, the rates for all groups were below replacement.

Q: Is there a finding in this report that surprised you?

BH: The range between the highest and lowest total fertility rate among the states by race and Hispanic origin groups is noteworthy. As we mentioned, for non-Hispanic white women, the TFR for Utah was more than double the TFR for the District of Columbia. For non-Hispanic black women, the TFR for Maine was 3.5 times higher than that for Wyoming. For Hispanic women, the TFR for Alabama was 2.6 times higher than the TFR for Vermont.