This open access book describes the differences in US census coverage, also referred to as “differential undercount”, by showing which groups have the highest net undercounts and which groups have the greatest undercount differentials, and discusses why such undercounts occur. In addition to focusing on measuring census coverage for several demographic characteristics, including age, gender, race, Hispanic origin status, and tenure, it also considers several of the main hard-to-count populations, such as immigrants, the homeless, the LBGT community, children in foster care, and the disabled. However, given the dearth of accurate undercount data for these groups, they are covered less comprehensively than those demographic groups for which there is reliable undercount data from the Census Bureau. This book is of interest to demographers, statisticians, survey methodologists, and all those interested in census coverage.

The Statistical Abstract of the United States, published since 1878, is the standard summary of statistics on the social, political, and economic organization of the United States. It is designed to serve as a convenient volume for statistical reference and as a guide to other statistical publications and sources. The latter function is served by the introductory text to each section, the source note appearing below each table, and Appendix I, which comprises the Guide to Sources of Statistics, the Guide to State Statistical Abstracts, and the Guide to Foreign Statistical Abstracts.

The population and housing census is part of an integrated national statistical system, which may include other censuses (for example, agriculture), surveys, registers and administrative files. It provides, at regular intervals, the benchmark for population count at national and local levels. For small geographical areas or sub-populations, it may represent the only source of information for certain social, demographic and economic characteristics. For many countries the census also provides a solid framework to develop sampling frames. This publication represents one of the pillars for data collection on the number and characteristics of the population of a country.