Breakaway gap on SPY

Buyers keep pressing into the major equity ETFs, with SPY and QQQ recently hitting their highs of the day. For both, there is a potential that this is a "breakaway gap", where buyers are so eager to get in that there is a gap between today's low and yesterday's close.

When SPY has seen this kind of behavior before, it tended to fall back the next day, and had mediocre returns in the short-term in general, but showed decent performance over the next month.

It took a median of 14 days for SPY to fill the gap, meaning it closed below the price prior to the gap open. But there was wide variability among them, with several of them taking more than 3 months. There were 4 that went unfilled for at least 6 months, not including the most recent couple of gaps.

It's tenuous, but we could gingerly conclude that behavior like this is unlikely to be a true breakaway that never sees a price that trades below Friday's close.