Which States Have The Most Think Tanks?

Washington, DC is clearly the think tank capital of the world, with 393.  Following is the top ten list, according to the latest statistics.  You can find the statistics for all of the states in that report.

1. Washington, DC: 393
2. Massachusetts: 176
3. California: 170
4. New York: 144
5. Virginia: 106
6. Illinois: 55
7. Maryland: 49
8. Texas: 47
9. Connecticut: 46
10. Pennsylvania: 41