"This report focuses on the evaluation of the assumptions about emigration of the native born used by the Census Bureau. From the 1970s through the 1980s, the Census Bureau estimated annual emigration of the native born at a constant level of 27,000. For the 1990 and 2000 decennial population census, the Census Bureau estimated annual emigration of the native born at a constant level of 48,000. The evaluation attempted- unsuccessfully- to replicate the approach taken to arrive at the 48,000 figure. However, working with published data from population censuses and statistical reports of other countries, we were able to calculate a rough estimate of the net effect of the native born emigrant flow on the 2000 national resident population estimate. We compared the available data for dates as close to 1990 and 2000 as possible for 16 countries for which data were available. These 16 countries represented 58 percent of the American population abroad as measured by 2000 State Department data. We then applied 1990 U.S. survival rates to survive the populations of the 11 countries for which age distribution data were available. For those countries for which we did not have age distributions, we estimated the survived population by assuming a one- percent annual decrease in the Year 1 population. This was based on the experience of the countries for which we did have data. The limitations on the available data make the estimate of the native born emigrant population questionable, but our research indicates that the magnitude of this population is small and likely to fluctuate over time. Our best estimate of the annual emigration of the native born is 18,000, or 180,000 for the 1990-2000 intercensal decade. Based on this estimate, we believe that the estimate of 480,000 native born emigrants for the 1990-2000 decade that was used in the 2000 national population estimate is too high by 300,000."
Population Division Working Paper #63
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