From the Open Secrets blog Capital Eye, the Federal Election Commission put out a release showing a 1.3% increase in the number of registered political action committees over the last seven months. The best part of this release by the FEC is a long chart detailing PAC registrations from 1974 to the present. I broke down this down into some cool charts below:

As Massie Ritch points out at Capital Eye, corporate PACs outpaced others, particularly labor PACs, by quite a bit. That wasn’t always the case: