This report discusses in detail recent experimentation involving the use of data from the Social Security Administration's Continuous Work History Sample of persons in covered employment for the purpose of directly measuring net migration for States and SMSA's.

Part I: Nature, coverage, and utility of the Work History File, reviews the nature of the Work History File, its coverage, its limitations, and procedural problems associated with its use for measurement of resident migration. Estimates of net migration derived from the File for regions, States, and SMSA's by race for 1960-65 are compared with closely corresponding estimates from other sources, such as the 1960 census, postcensal surveys, and independent population estimates.

Part II: Experimental estimates of State population by color, based on Work History File, July 1, 1965, provides an example of the direct application of these data to the Bureau's program of population estimation. It contains estimates of the population of States by age and color for July I, 1965, based almost entirely on Social Security data, i.e., through the use of migration rates from the Work History File to derive estimates of the population under 65, and Medicare figures to obtain the population 65 years of age and over.