The Puell Ratio is the ratio of today's supply divided by the average supply of the last 365 days - it explores market cycles from a mining revenue perspective. The ratio allows you to gauge the local level of supply in the context of the recent past. High values of the Puell ratio have shown to gauge high supply and therefore bearish price action. On the other hand, Low values of the Puell ratio have shown to gauge low supply and therefore bullish price action.
There are periods of time where the value of Bitcoins being mined and entering the system is too large or little relative to historical norms - understanding these periods can really help Bitcoin investors forecast what could happen next.