Reagan actually increased taxes, and increased federal spending in some areas, but I can say that Reagan was not a smart man, he didn't come up with "Reaganomics", his cabinet/lobbyists did, and he was fortunate enough that the concept worked.
Despite a similarity I draw to Keynesian econmics, as the national deficit soared during his administration, and shit was wonderful.
I'm too lazy to back up my shit with sources, someone do it for me.