The National Center for Health Statistics keeps data for each year going back to 1909 on the number of live births in the United States and on the fertility rate. Fertility rate is defined as the number of births per 1,000 women. These data are an important environmental concern because they greatly influence future population. The more people there are in the world, and the higher their standard of living, the more environmental stress is created. The United States has a high standard of living, so an increasing population here increases environmental strain.

Figure 1. Data source: National Center for Health Statistics Data Visualization Gallery; Martin et al., 2018.
Figure 1 shows the trend in births and fertility rate from 1909 to 2016. Live births are shown in blue, and should be read against the left vertical axis. The fertility rate is shown in red and should be read against the right vertical axis. In 1909 there were 2,718,000 live births, rising to a peak of 4,316,233 in 2007, and easing since then to 3,945,875 in 2016. In 1909 the birth rate was 126.8. It fell sharply to 75.8 in 1936 (the depths of the Great Depression), then increased sharply to 122.9 in 1957 (the baby boom). It then decreased sharply until the 1970s, and has trended slowly down since then. In 2016, the fertility rate was 62.0.
(Click on chart for larger view.)
Birth and fertility rates are also important from several other policy perspectives The NCHS report shows that the fertility rate is declining among all age groups under 30 years old, and the rate of teen births has been cut by more than half since 2007. This is a very important change for public health and welfare. The fertility rate for women over 30 has increased over time. In fact, the fertility rate for women in their 30s was 102.7 in 2016, compared to 73.8 for women aged 20-24, and 102.1 for women aged 25-29. Thus, more older women are giving birth.
In Missouri, data on the number of births goes back to 1990, when there were 79,135. Births then decreased to a low in 1995 of 72,804, after which they increased to 81,833 in 2007. Since 2007, they have declined to 74,664 in 2016. The fertility rate statistic is only available from 1996, when it was 61.4. It increased to 68.8 in 2007, and has declined since then, to 63.7 in 2016. The data is shown in Figure 2. The blue line is for the number of births, and should be read against the left vertical axis. The red line is for the fertility rate, and should be read against the right vertical axis.
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Figure 3 shows the 2016 fertility rate for the 50 states plus the District of Columbia. South Dakota had the highest fertility rate, at 77.7, and Vermont had the lowest, at 50.3. Missouri was 19th highest. I don’t think that anybody believes that state boundaries control fertility rate, but these data give a small snapshot of what is happening in our state compared to others.
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Sources:
National Center for Health Statistics Data Visualization Gallery (data portal). Data downloaded 3/28/2018 from https://www.cdc.gov/nchs/data-visualization/natality-trends.
Martin JA, Hamilton BE, Osterman MJK, Driscoll AK, Drake P. Births: Final data for 2016. National Vital Statistics Reports; vol 67 no 1. Hyattsville, MD: National Center for Health Statistics. 2018. https://www.cdc.gov/nchs/data/nvsr/nvsr67/nvsr67_01.pdf.
Missouri Department of Health and Senior Services. Missouri Information for Community Assessment Data Portal. Data downloaded 3/28/2018 from https://webapp01.dhss.mo.gov/MOPHIMS/MICAHome.