Fair representation in the House of Representatives has been a contested topic since the drafting of the United States Constitution in 1787.
Having freed itself from British rule and having outlasted the inadequacies of the Articles of Confederation, the United States of America determined the country needed some form of centralized government. How that government was to be structured, and what the proper standard for fair representation to that government would be, were just two of many problems facing the delegates to the Constitutional Convention.
After months of debate and failed compromises, the Founding Fathers decided on a calculation to determine each state’s relevant population. Representatives would then be allocated based on that number. This process has come to be known as congressional reapportionment. The calculation relied on a decennial census to determine the population through a person-by-person canvassing of the vast new country. The method agreed upon was controversial; even in 1787.
Alexander Hamilton and James Madison penned five Federalist Papers, (54, 55, 56, 57 and 58) in defense of the agreed upon method. They argued the process would overcome demographic shifts and population growth if a periodic redistribution of representation based on census figures was enacted.
Regarding the population used for apportionment:
“The apportionment population base always has included those persons who have established a residence in the United States. ... Prior to 1870, the population base included the total free population of the states, three-fifths of the number of slaves, and excluded American Indians not taxed. The 14th Amendment, ratified in 1868, removed the fractional count of the number of slaves from the procedure.” – via the Census Bureau
The method of reapportionment has changed four times in the 229 years following its inception, but the data for it has always come from a decennial national census.The Method of Equal Proportions was first used in 1941 and is still in use today. It assigns a priority value to every seat in each state, until all 435 members are allotted; a number set by a federal statute in 1911. Aside from temporary districts for Alaska and Hawaii in 1959, that number has remained constant.
The Census Bureau last allocated Congressional seats on December 21, 2010.
Reapportionment sent 11 seats from the Northeast and Upper Midwest to the South and West in 2010.
Ten years earlier, a similar 10-seat transfer occurred. The changes so far in the 21st Century have resulted in New York losing 4 members, Ohio and Pennsylvania each losing 3, and Michigan and Illinois both dropping 2. Over the same period Texas increased by 6 members, Florida by 4, Arizona and Georgia by 3 each, and Nevada by 2.
Current trends are projected to continue in 2020, when the next decennial census will determine representation for the coming decade.