1%

I think Perry is talking about how to be part of a political or social group, you have to trade off your individuality and let others hold you down, and he is saying that, that is too big of a price to pay as far as he is concerned.

Janes addiction is awesome

biggest gang i know they call the government gang is a weapon that you trade your mind in for you gotta be just - be just like them the gang and the government no different

That is such a good lyric!

Sounds like disdain for the government and their two-faced ways.

I think he's also saying that since the government is the biggest gang of all and since there are all sorts of "gangs"(social groups, political parties, even actual gangs) the world over, and since he doesn't seem(in the song, at least) to belong to or care about any of them, then he(and others like him) make us less than 1% of the world(because the world is mostly or seems to be most about groups).

I don't know if it's relevant to the song, but 1% is also term used by the Hell's Angels. They consider themselves to be the 1% that have rejected society's values and are doing their own thing. I think this is Perry's way of embracing that concept of individuality