Compounding works both ways

Compounding means earning returns on your past returns. Invest one hundred at seven percent and in ten years you have about one ninety seven. In thirty years, about seven hundred sixty. The curve is flat for a long time, then steep. The same curve applies to debt. A card balance at twenty four percent doubles in about three years if nothing is paid. Time is the multiplier in both cases. The only question is which side of it you stand on.