This report presents detailed social and economic characteristics of the United States population below the poverty level in 1984 based on the March 1985 Current Population Survey. Poverty data are cross-classified by such characteristics as race, family relationship, type of residence, education, work experience, and type of income received. Estimates in the report were developed from two sample frames: one from the 1970 census, and the other from the 1980 census. General findings are described in a brief introduction, but the bulk of the report consists of statistical tables, organized into three groups: trends in poverty population, persons, and families. A major finding was that the poverty rate declined for both whites and blacks between 1983 and 1984. No statistically significant changes were recorded in the number or percent of Spanish-origin persons in poverty. Between 1983 and 1984, the total number of poor families declined as did the number of poor married-couple families. The number of persons below the poverty level and the poverty rate declined in the South and West Regions, while the Northeast and Midwest Regions did not experience any significant changes. The poverty rate for the South was 16.2 percent, higher than any other region. Four appendices consist of: definitions, explanation, and discussion of the comparability of data; description of the source and reliability of data; an analysis of the problem of underreporting of income; and facsimiles of the March 1985 current Population Survey questionnaires. (KH)