Almost every belief system works the same way for those devoutly committed to a belief. And that includes political beliefs. Political parties are the central banks that store ideas for a price, that is, for maintaining the belief system.
As long as people keep hoarding, i.e., keep holding onto, their ideas rather than spending them in philosophical debate and idea exchange, negative interest rates will govern the economy of the political mind.
Wish for a positive return on your intellectual treasure? Go out and spend some ideas in debate. If others begin to spend similarly, the economy of the mind will emerge from its long recession.