Nine out of ten. That is how Rubico's own history reads after a pop, and it is also the reason not to lean on it too hard.
$RUBI is +35.39% pre-market. It is a $2M company with about 2M shares of float. The latest item in the feed is a 6-K dated yesterday, a foreign private issuer's material-event report. Nothing sourced here ties it to this morning, so the move is unexplained.
Rubico has 10 prior sessions that opened at least 5% above the prior close. Nine of them closed below the open and one closed above it. The median open-to-close move was -16.57%, and the mean was -22.02%.
That is a violent skew from a tiny sample. Ten sessions is a pattern worth writing down, not a law. And a 5% threshold puts modest pops and a gap this size in the same bucket, so this morning is not a clean match for any of those ten.