General, Age-Specific, and Total Fertility Rates in Montana, 2008-2017

Matthew Ringel
Montana Department of Public Health and Human Services


Fertility rates have been steadily declining in the United States over the past several years, and this trend may have implications for the economy and for other elements of society. Some are concerned as declining fertility rates may be indicative of economic anxiety and could also cause future problems for the economy due to dwindling number of workers and consumers. Other see this as a positive change because it could indicate higher education and career achievement among women and it could lead to decreased consumption and pollution. Either way, this trend may be of interest to federal, state, and local governments. This paper shows readers how to use SAS to calculate general, age-specific, and total fertility rates and how to use linear regression to test for a significant trend. It uses Montana Birth Data and National Center for Health Statistics (NCHS) Population Data to illustrate the process. In Montana, between 2008 and 2017, there was a significant downward trend in both the general fertility rate and the total fertility rate. This trend was largely due to a substantial reduction in births among women between the ages of 15 and 24 and may be due to women delaying childbirth for educational purposes. Therefore, there is reason to believe that the current low total fertility rate may be temporary. This trend should be monitored into the future to see if it continues or reverses course.