FOMC drift
The positive drift into FOMC rate announcements is well-known and has persisted for a long time. It typically doesn't last all that long, though. Below, we can see returns in SPY from the open on the day of a FOMC announcement since April. The only one that showed meaningful sustained gains over the next week or so was in July, coming on the heels of what had been a minor decline. The others occurred after stocks had already rallied.

