Study Search Results Your query returned 3 results. Series results are grouped under the most relevant study. You can ungroup series results. Results per page: 25 50 100 Sort by: Title A-Z Released/Updated Time Period Most Cited in ICPSR Bib. (?) Study Title/Investigator 1. Census of Population and Housing, 1980 [United States]: Summary Tape File 5, Special Tabulations of Population 60 Years and Over (ICPSR 8658) United States Department of Commerce. Bureau of the Census 2. Old Age in the United States, 1880 (ICPSR 8427) Jensen, Richard; Smith, Daniel Scott; Friedberger, Mark W.; et al. 3. Old Age in the United States, 1900 (ICPSR 8428) Jensen, Richard; Smith, Daniel Scott; Friedberger, Mark W.; et al.