Reapportionment Winners and Losers Through the Years

Pennsylvania (-17 seats) and New York (-16 seats) have lost the largest number of seats from their peak U.S. House delegations; the Keystone State is slated to lose a seat again for a 9th consecutive census period

With millions of U.S. Census forms turned in to the federal government this spring, the process of counting heads in each of the 50 states to determine their respective level of representation in the U.S. House is well underway.

Several projections have been conducted by experts during the last few years - with Texas and Arizona universally considered to be the big winners of multiple seats, with the remaining gains coming from states in the southern and western regions of the country: Nevada, Utah, Florida, South Carolina, and Georgia. (Oregon and North Carolina might also gain seats).

Most states projected to lose seats, meanwhile, are located in the Northeastern and Midwestern regions - Ohio, New York, New Jersey, Pennsylvania, Massachusetts, Illinois, Iowa, Michigan, Minnesota, and Missouri. (Louisiana is also projected to lose a seat and potentially California).

Population shifts, and the resulting reapportionment, caused by the expansion and settling of a new nation are expected, of course, but there has also been great fluctuation in the apportionment of seats to the U.S. House even after membership was (largely) stabilized at 435 voting members after the 1910 census.

Pennsylvania has suffered the largest number of lost seats over the years - losing 17 seats from their peak U.S. House delegation of 36 members after the 1910 Census to 19 seats today.

Pennsylvania has lost seats for a record eight consecutive census periods, beginning with the 15th Census in 1930 through the 22nd Census in 2000, and are expected to lose another seat after the 2010 Census.

Neighboring New York has also endured a significant drop in seats to the U.S. House. After holding steady at 45 seats after the 1930 and 1940 Censuses, the Empire State has lost seats in six consecutive census periods, shedding 16 seats in total to its current level of 29 seats today.

Two other states have lost seats by double-digit margins from their peak representation in the U.S. House - Virginia (-12) and Massachusetts (-10). However, each of these states reached their peak levels after the 1810 Census, when the country was comprised of just seventeen states. Virginia had 23 seats at that time, or 12.7 percent of the 181-seat U.S. House of Representatives, with Massachusetts at 20 seats, or 11.0 percent.

In total, 34 states currently have a U.S. House delegation that is smaller than its peak historical level.

· Vermont has lost the largest percentage of seats over the decades, from a high of 6 seats after the 1810 Census to its current level of 1 seat today - a drop of 83 percent.

· Maine has lost 75 percent of its seats from a high of 8 seats after the 1830 Census to just 2 seats today.

· New Hampshire (6 to 2), North Dakota (3 to 1), and South Dakota (3 to 1) have also lost two-thirds of their seats to the U.S. House over the years.

· The current U.S. House delegation of another three states is more than 50 percent smaller than its previous peak level: Iowa (-55 percent; 11 to 5 seats), Kentucky (-54 percent; 13 to 6 seats), and Virginia (-52 percent; 23 to 11 seats).

Meanwhile, the U.S. House delegations from 13 other states across the country are currently at their highest levels to date: California (53 seats), Texas (32), Florida (25), Georgia (13), North Carolina (13), Washington (9), Arizona (8), Colorado (7), Oregon (5), New Mexico (3), Nevada (3), Utah (3), and Idaho (2).

There has been a consistent, upward trajectory in the number of delegates allocated to all but two of these states (North Carolina and Georgia) - rising or holding steady each decade since they were admitted into the union.

(North Carolina had previously been allotted 13 seats after the 1810, 1820, and 1830 Censuses, only to fall to a low of 7 seats after the 1860 Census and then increase, decrease, and increase again to reach its current level of 13 seats after the 2000 Census. Georgia has also experienced significant fluctuation over the decades).

Another three states - Alaska, Hawaii, and Wyoming - have been awarded the same number of seats to the U.S. House after each census period since statehood (one, two, and one respectively).

Delaware holds the record for the longest stretch at the same number of seats, receiving just one at-large seat across the 4th through 22nd Censuses dating back to 1820.

Change in Apportionment by State Since Peak Levels

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