Movement of Congressional Power from 1960-2010

The other day, when talking about my upcoming trip around America with a friend very involved in US politics, he mused that it would be interesting to see how the representation of each state in the House of Representatives has changed since 1960, given the south- and west-ward shift in population over the last 50 years.

As a quick refresher (mostly for myself), each state is given a percentage of the total 435 delegates based on the population of that state. Thanks to Wikipedia, I found US Census population numbers for 1960 onward. I calculated the percentage of each state's population versus the total US population, then took the same percentage of the total 435 delegates in the House of Representatives. (Note: after initial publication of this entry, I discovered the US Census apportionment document as a PDF. I have not yet updated the map, but the numbers are very close.)

Because of complex apportionment rules, my initial results were inaccurate; because of this, please view the maps with this caveat: the maps give a general idea of how numbers of representatives have changed, not exact representation. The results are shown in the image above and in the interactive display below. Additionally, results can be viewed as a live map on Carto's site.

Notice the decline in power from the Northeast: New York lost 14 delegates, Pennsylvania 9, and Ohio 8. Meanwhile, California, Texas, and Florida all gained in the double digits.

Please note this map can be slightly misleading (as all maps can be): click on each state in the interactive map to see the number of current and past delegates.

For example, red-colored New York is down to 27 delegates, but still has the same number as green-colored Florida. This map is designed to illustrate change from 1960 to 2010 in order to better understand overall population shift, not to show the current state of affairs.

For directions on how to "lie" with maps and a lesson in how easy it is to be misled, check out the seminal book from the University of Chicago Press, a must-read for any aspiring geographer.