You need to have a cycle of continually devaluing issued money that sits in store to encourage circulation, and reissue new money at the same time to make up for the difference. This is the best way to control the amount of money in circulation to match the size of the economy.

If money isn't circulating its amount can't be regulated. You can only reduce the value of money by printing more of it which is a poor hack that governments worldwide are doing because they don't have demurrage. This way prices will vary (meaning increase) but still in a somewhat controlled and predictable way as opposed to the wild fluctuations we would have with no control over the supply.

Silvio Gesell's "The Natural Economic Order" does a pretty good job explaining it, or the movie "Shillings from Heaven" as a teaser maybe.