Abstract
Interstate elderly migration has strong implications for state tax policies and health care systems, yet little is known about how it has changed in the twenty-first century. Its relative rarity requires a large data set with which to construct reliable measures, and the replacement of the U.S. Census long form (CLF) with the American Community Survey (ACS) has made such updates difficult. Two commonly used alternative migration data sources—the Current Population Survey (CPS) and the Statistics of Income (SOI) program of the Internal Revenue Service (IRS)—suffer serious limitations in studying the migration of any subpopulation, including the elderly. Our study informs migration research in the post-2000 era by identifying methodological differences between data sources and devising strategies for reconciling the CLF and ACS. Our investigation focusing on the elderly suggests that the ACS can generate comparable migration data that reveal a continuation of previously identified geographic patterns as well as changes unique to the 2000s. However, its changed definition of residence and survey timing leaves us unable to construct a comparable national migration rate, suggesting that one must use national trends in the smaller CPS to investigate whether elderly migration has increased or decreased in the twenty-first century.
Similar content being viewed by others
Notes
Ruggles (2013:293) touted the importance of such data as well; while offering advances for migration researchers, the discontinuity in U.S. data caused by the switch to the ACS was not discussed. Similarly, the problems caused by this discontinuity are not addressed in recent work that combines the two sources to study patterns over time (e.g., Iceland et al. 2012).
See also https://www.census.gov/hhes/www/poverty/about/datasources/factsheet.html for a comparison of the survey methodology and population universe of the CPS and ACS, and Willekens (2016) for a more general discussion of the challenges and issues in measuring migration.
The standard error formula is \( \sqrt{p\left(1-p\right)/n} \), where p is the proportion who migrate, and n is the sample size. Across all data sources, the standard error for the total population is approximately one-half the size of the elderly’s, whereas the migration rate (p) is more than twice as large. The full set of calculations is available upon request.
Willekens (2016) pointed out that the population at risk is difficult to define for a net migration rate because the rate captures those moving into the state from other places. Still, one must adjust for population size, and this approach is common.
This measure is similar to that reported by past over-time comparisons and updates of elderly migration (e.g., Flynn et al. 1985; Longino and Bradley 2003) except that they focus on in-migrants and out-migrants separately rather than flows. See also Rogers and Raymer (1998), who discussed alternative measures of spatial focus and recommend the coefficient of variation (CV). Results based on the CV confirm our conclusion regarding concentration.
During any given time interval, individuals can move multiple times such that the number of moves exceeds the observed number of migrants. A longer interval also increases survivor bias because individuals must survive to an older age to be observed (e.g., age 85 vs. 81 for a move made at age 80). This bias is especially acute for the elderly. For both reasons, the number of moves and migrants missed grows with the length of the interval.
Details of these calculations are available upon request.
The CVs for each year (4.7, 3.9, 3.2, and 2.5, respectively) also show a decline in concentration.
References
Bean, F., Myers, G. C., Angel, J. L., & Galle, O. R. (1994). Geographic concentration, migration and population redistribution among the elderly. In L. G. Martin & S. H. Preston (Eds.), Demography of aging (pp. 319–355). Washington, DC: National Academies Press.
Bradley, D. E., & Longino, C. F. (2009). Geographic mobility and aging in place. In P. Uhlenberg (Ed.), International handbook of population aging (pp. 319–339). New York, NY: Springer.
Conway, K. S., & Rork, J. C. (2010). “Going with the flow”—A comparison of interstate elderly migration during 1970–2000 using the (I)PUMS versus full census data. Journals of Gerontology, Series B: Psychological Sciences and Social Sciences, 65B, 767–771.
Conway, K. S., & Rork, J. C. (2012). No country for old men (or women)–Do state tax policies drive away the elderly? National Tax Journal, 65, 313–356.
Flynn, C. B., Longino, C. F., Wiseman, R. F., & Biggar, J. C. (1985). The redistribution of America’s older population: Major national migration patterns for three census decades, 1960–1980. Gerontologist, 25, 292–296.
Franklin, R. S., & Plane, D. A. (2006). Pandora’s box: The potential and peril of migration data from the American Community Survey. International Regional Science Review, 29, 231–246.
Gross, E. (2014). U.S. population migration data: Strengths and limitations. Retrieved from http://www.irs.gov/pub/irs-soi/99gross_update.doc
Iceland, J., Sharp, G., & Timberlake, J. M. (2012). Sun Belt rising: Regional population change and the decline in black residential segregation, 1970–2009. Demography, 50, 97–123.
Kaplan, G., & Schulhofer-Wohl, S. (2012). Interstate migration has fallen less than you think: Consequences of hot deck imputation in the Current Population Survey. Demography, 49, 1061–1074.
Lin, G. (1999). Assessing changes in interstate migration patterns of the United States elderly population, 1965–1990. International Journal of Population Geography, 5, 411–424.
Longino, C. F., & Bradley, D. E. (2003). A first look at retirement migration trends in 2000. Gerontologist, 43, 904–907.
Molloy, R., Smith, C. L., & Wozniak, A. (2011). Internal migration in the United States. Journal of Economic Perspectives, 25, 173–196.
National Research Council. (2006). Once, only once, and in the right place: Residence rules in the decennial census. Panel on Residence Rules in the Decennial Census. D. L. Cork & P. R. Voss (Eds.), Committee on National Statistics, Division of Behavioral and Social Sciences and Education. Washington, DC: National Academies Press.
Newbold, K. B. (2011). Migration and regional science: Opportunities and challenges in a changing environment. Annals of Regional Science, 48, 451–468.
Raymer, J., & Rogers, A. (2007). The American Community Survey’s interstate migration data: Strategies for smoothing irregular age patterns (Population Program Working Paper No. POP2007-08). Boulder: University of Colorado Population Program, Institute of Behavioral Science.
Rogers, A., & Raymer, J. (1998). The spatial focus of US interstate migration flows. International Journal of Population Geography, 4, 63–80.
Rogers, A., Raymer, J., & Newbold, K. B. (2003). Reconciling and translating migration data collected over time intervals of differing widths. Annals of Regional Science, 37, 581–601.
Ruggles, S. (2013). Big microdata for population research. Demography, 51, 287–297.
Sergeant, J. F., Ekerdt, D. J., & Chapin, R. (2008). Measurement of late-life residential relocation: Why are rates for such a manifest event so varied? Journals of Gerontology, Series B: Psychological Sciences and Social Sciences, 63, S92–S98.
Uhlenberg, P. (2006). Migration. In R. Schulz (Ed.), The encyclopedia of aging (pp. 777–780). New York, NY: Springer.
Van Auken, P. M., Hammer, R. B., Voss, P. R., & Veroff, D. L. (2006). The American Community Survey in counties with “seasonal” populations. Population Research and Policy Review, 25, 275–292.
Walters, W. H. (2002). Later-life migration in the United States: A review of recent research. Journal of Planning Literature, 17, 37–66.
Willekens, F. (2016). Migration flows: Measurement, analysis and modeling. In M. J. White (Ed.), International handbook of migration and population distribution (Vol. 6, pp. 225–241). Dordrecht, The Netherlands: Springer. Retrieved from http://link.springer.com/10.1007/978-94-017-7282-2_11
Wolf, D. A., & Longino, C. F. (2005). Our “increasingly mobile society”? The curious persistence of a false belief. Gerontologist, 45, 5–11.
Acknowledgments
We thank the Editors, referees, and participants in our session at the Population Association of America annual meetings for their helpful comments.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Conway, K.S., Rork, J.C. How Has Elderly Migration Changed in the Twenty-First Century? What the Data Can—and Cannot—Tell Us. Demography 53, 1011–1025 (2016). https://doi.org/10.1007/s13524-016-0477-7
Published:
Issue Date:
DOI: https://doi.org/10.1007/s13524-016-0477-7