Historically, a 3% dip takes place on average every 1-3/4 months and a 5% dip every 3-1/2 months. We haven't had more than a 2% dip in over 3-1/2 months $SPX
In the past 10 yrs, the current rally without even a 3% dip is equal in time to the ones that ended in Feb 2017 and Jan 2020 (red circles). The only longer rally (by nearly 3 times) ended in Jan 2018 (green)