Data and Methods
These data include estimates of net migration for US counties by five-year age group, sex, and race each decade from the 1950s through the first decade of the 2000s. The 1990s and 2000s also include estimates by Hispanic origin. Net migration is the balance of in-migrants minus out-migrants. The data do not include flows of in-migrants or out-migrants, but only the net balance. Age refers to age at the end of the decade. See the data dictionary to learn more.
Data were generated using a residual method based on US Census counts at the beginning and end of each decade and intercensal birth and death records. The population counted at the beginning of the decade is aged forward over time, subtracting out deaths and adding in births, to generate an "expected population" at the end of the decade. The observed population counted in the census at the end of the decade is then subtracted from the expected population to estimate the number of net migrants. Because the estimates do not rely on sampling, they are highly accurate and reliable. Learn more about this method.
Net migration estimates were generated following this general process each decade by different research teams to create a coherent dataset spanning 60 years of age-specific net migration for US counties (1950s: Bowles and Tarver 1965; 1960s: Bowles, Beale and Lee, 1975; 1970s: White, Mueser and Tierney 1987; 1980s: Fuguitt and Beale 1993; 1990s: Voss, McNiven, Johnson, Hammer, and Fuguitt 2004; 2000s: Winkler, Johnson, Cheng, Voss, and Curtis). Paul Voss and the team who put together the estimates for the 1990s deserve special recognition for integrating data from prior decades with the 1990s and constructing charts similar to those you see here. Jim Beaudoin at the Applied Population Laboratory at the University of Wisconsin- Madison designed this website and its applications.
To facilitate comparison over time, the charts in this website combine some counties into groupings where boundaries have changed over the decades. Other counties are missing data from prior decades. This process generates 3,095 county observations plus 50 states (total n= 3,145) in the dataset that the charts, maps, and data download reference. A summary of counties affected by these boundary changes is available. You can find net migration estimates for counties in their temporally consistent boundaries in the full datasets described below for each decade.
You may also download the full dataset for the 2000s, including detailed documentation.
In addition to being available here, data from prior decades are available for download at ICPSR.
Support for the generation of these data has come from various sources and institutions over the last sixty years. The 2000-2010 project, including construction of this website, was supported by Grant Number 7R03HD069737-02 from the Eunice Kennedy Shriver National Institute of Child Health and Human Development. Additional support was provided by the U.S. Department of Agriculture, Economic Research Service, Joint Research Agreement No. 58-6000-0-0055. The content is solely the responsibility of the authors and does not necessarily represent the official views of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, the National Institutes of Health, or the United States Department of Agriculture.
Work on the current project was conducted in the Department of Social Sciences at Michigan Technological University, the Applied Population Laboratory at the University of Wisconsin- Madison, and the Carsey Institute at the University of New Hampshire.
Please contact Richelle Winkler with questions or comments about the data or the project.
Please contact the Applied Population Lab with technical difficulties or with suggestions for improving this website.
1950s: Bowles, G. K. and J. D. Tarver. 1965. Net Migration of the Population, 1950-60, by Age, Sex and Color. Washington, D.C.: U.S. Department of Agriculture, Economic Research Service.
1960s: Bowles, G. K., C. L. Beale, and E. S. Lee. 1975. Net Migration of the Population,1960-70, by Age, Sex and Color. Washington: U.S. Department of Agriculture, Economic Research Service and Athens: University of Georgia.
1970s: White, M. J., P. Mueser, and J. P. Tierney.1987. Net migration of the population of the United States 1970-80, by age, race and sex. (Computer file with documentation.) Ann Arbor, MI: Inter-university Consortium for Political and Social Research.
1980s: Fuguitt, G. V., C. L. Beale, and P. R. Voss. 2010. County-Specific Net Migration Estimates, 1980-1990. ICPSR26761-v1. Ann Arbor, MI: Inter-university Consortium for Political and Social Research, 2010-04-02. doi:10.3886/ICPSR26761
1990s: Voss, P. R., S. McNiven, R. B. Hammer, K. M. Johnson, G. V. Fuguitt. 2004. County-specific net migration by five-year age groups, Hispanic origin, race and sex 1990-2000. CDE Working Paper No. 2004-24. Center for Demography and Ecology, University of Wisconsin-Madison. Madison, WI.
2000s: Winkler, R.L., K. M. Johnson, C. Cheng, P.R. Voss, and K.J. Curtis. 2013. County-specific net migration by five-year age groups, Hispanic origin, race and sex 2000-2010. CDE Working Paper No. 2013-04. Center for Demography and Ecology, University of Wisconsin-Madison. Madison, WI.