the highest level since 1940 (the earliest census for which estimates of this type are available). Differential undercounts for blacks, Hispanics, and others cause concern because of their implications for such important uses of census information as legislative redistricting and fund allocation. Second, the existence of an initial census count and a subsequent and separate estimate from a postcensal evaluation survey for 1990 gave rise to divisive political arguments and legal suits over which set of numbers would be the official ones to be used for these important purposes.
Third, the costs of taking the census have escalated sharply, even after allowing for inflation and population growth. One of the reasons for that cost escalation, disturbing in its own right, has been a drop in the percentage of households who cooperate by filling out and returning the mail questionnaire. The 1970 decennial census cost $231 million. If adjustments are made to reflect the rise in prices and wages and the growth in the number of households between 1970 and 1990, with a further adjustment to take account of the increased costs associated with the decline in the mail response rate, the cost of conducting a 1970-type census in 1990 would have been about $1.3 billion. The actual cost of the 1990 census was $2.6 billion, twice as much. Although it has been argued that a major cause of the cost increase was due to costs associated with the long form (the longer questionnaire sent to 1 in 6 housing units in 1990), the panel's analysis of the relationship of content and cost led us to conclude that the content of the census did not produce the added costs. More generally, the panel has found that moderate changes in content do not have a significant effect on census costs.
In spite of considerable effort, the panel was unable to pin down, item by item, the causes of the cost increases. The panel believes, however, that a major part of the cost increase was driven by the response of the Census Bureau to several outside pressures. Most important, there was an increased and politically powerful demand for accurate population counts for very detailed geographical subdivisions and in hard-to-enumerate areas. Simultaneously, public cooperation with the census process, as measured by mail response rates, declined and was lowest in precisely those areas for which the pressures for an accurate count were greatest. The Census Bureau responded by pouring on resources in highly labor-intensive efforts to attempt to count every last person.
The panel's first task was to investigate whether and to what extent various types of essential data can best be collected by the decennial census or by other means. Our second task was to consider and recommend the most cost-effective methods of conducting the census and otherwise collecting census-type data. We evaluated a wide range of methods for meeting the requirements of the decennial census, including radical proposals that would sharply alter the way