Article I, Section 2, of the U.S. Constitution requires that every ten years an “actual Enumeration” — or a full count of the residents in our country — be undertaken. As James Madison stated in Federalist No. 58, the census was required in large part to determine representation of the states to the House of Representatives. The decennial census has occurred every ten years since 1790, regardless of economic condition, wars, or other challenges this nation faced.
The census relies heavily on self-reporting — a process where individuals are asked to complete and return a questionnaire. For those who do not self-report, the government uses enumerators who go to an individual’s residence in order to complete the census questionnaire, or the government uses less reliable counts by proxy. Previous census counts relied entirely on enumerators going door-to-door, like the 1940 census.
Throughout the history of the nation, each census has encountered challenges in counting every resident. For example, after the nation’s first census, both George Washington and Thomas Jefferson expressed doubts that there was a complete and accurate count. As George Washington lamented:
Returns of the Census have already been made from several of the States and a tolerably just estimate has been formed now in others, by which it appears that we shall hardly reach four millions; but one thing is certain: our real numbers will exceed, greatly, the official returns of them; because the religious scruples of some would not allow them to give in their lists; the fear of others that it was intended as the foundation of a tax induced them to conceal or diminish theirs; and thro’ the indolence of the people and the negligence of many of the Officers, numbers are omitted.
Ever since Washington wrote those words, there have been other examples of inaccurate counts, particularly of historically undercounts of minorities and children. While the census has become more accurate over time with improved social science, there are persistent issues reaching hard-to-count communities, many of which have higher percentages of minorities, foreign-born residents, children under five, renters, homeless, and low-income individuals. The result is chronic undercounting of key socioeconomic groups. While there is no formal definition of hard-to-count communities by the census, the City University of New York’s (CUNY) Mapping Service at the Center for Urban Research defines it as a community (or census tract) with a self-response rate of less than 73 percent. For the purposes of this report, we adopt CUNY’s definition as a baseline and further refine it in more detailed analysis.