Basically, it tells you the dip from the highest price in the lookback period to current price. If you want the real ATH, you need to select a big lookback that takes into account all the price history. You can also use a short lookback to make it more responsive to recent price changes. Backtest to see which one is better for your strategy.
A word of caution: I’ve tried to short the dump after the pump, and it’s very difficult. Definitely I don’t recommend any leverage.
If I were to try again I would use a 2-step bot setup: First DCA to get a good average price, then a short combo with a static price filter to only trade over your average price. That way it will only sell when you are already in profit.