The United States Constitution was a precedent-breaking document: The very idea of setting forth, in a single document, the structure of a republican government, and of providing a means for revising that structure and document, was novel and untested. One of its novelties was the creation of the first regularly scheduled national census of population — and the first national legislature whose composition was determined by population.
Other states had conducted censuses since ancient times: The Bible records that Joseph and Mary were in Bethlehem at the time of the birth of Jesus because Joseph was required to be in his ancestral town for a Roman census. Italian city-states had conducted censuses; 17th century English writers prepared detailed estimates of their nation’s population.
“Representatives,” states Article I, Section 2, “shall be apportioned among the several States which may be included within this Union, according to their respective Numbers.” Note that the Constitution specifically envisions the admission of new states, beyond the 13 represented at the Convention in Philadelphia.
The provision goes on, “The actual Enumeration shall be made within three Years after the first Meeting of the Congress of the United States, and within every subsequent Term of ten years, in such manner as they shall by Law direct.” In fact the first Congress provided for a census to be conducted in 1790 and in every tenth year ending in zero thereafter.
The linkage of population and representation was even more original. Congress has provided for several formulas to convert total populations for each state to integer numbers of representatives. After the 1920 census, Congress failed to do so, despite the constitutional command, partly because many members were repelled by the census’s finding that a majority of Americans lived in urban areas (defined as places with populations of 2,500 or more). But in 1930 Congress passed a law, still in effect today, establishing an arithmetic formula by which representatives would be apportioned to the states automatically from census data.
The number of representatives was set at 435, with the proviso that it could be temporarily increased after the admission of new states to the Union (as it was after Alaska and Hawaii became states in 1959), but that number could be changed at any time by act of Congress.
In recent political debate it has been argued that delegates to the Constitutional Convention, when they write the provision providing two senators for each state, could not have anticipated the vast differences in the population of states; the 2010 census showed that California had 67 times more residents than Wyoming. But of course they recognized the disparity: That is why delegates from the larger states advocated allocating representation by population and delegates from smaller states advocated equal representation for each state. The compromise was that Congress was made up of two houses, one with equal representation, the other with representation proportionate to population — and Article I, Section 2 was carefully crafted to provide as accurate as possible a determination of population.
Proof that the Framers had an accurate idea of the vast differences in the states’ populations is the formula in Article I, Section 2, for representation in the first Congress, before a census could be taken. Each state’s percentage of representatives under that formula and in the apportionment following the 1790 census were strikingly similar.
