This chart is the ratio between QQQ and SPY. When the ratio increases, it means QQQ is outperforming SPY.
Just recently the ratio broke out of a symmetrical triangle, and now we may be entering into an ascending channel (purple lines).
If we can manage to stay within the ascending channel, then it's safe to assume that QQQ could outperform SPY by 5 percentage points in the short term. E.g. if SPY returns 10% in a month, then QQQ returns 15% - a difference of 5 percentage points.
If we break out from the ascending channel and move higher, then QQQ could really outperform SPY.