The S&P 500 is down 2.1% today and hit a low of 3903, which is just below the mid-November low. It's since bounced back above that but the double top at 4100 and what's possibly a breakdown isn't a good look.
On the fundamental side, a lot of the optimism was about central banks being less hawkish and pivoting with inflation. Many people still think that's coming but it's going to take some more soft data points and a Fed climbdown. In the meantime, there will be headline after headline with the Fed trying to push up the terminal rate and year-end 2023 rate. That's a tough headwind and over the next week there's plenty of reason for tax-loss selling.
What also worries me is that the forward multiple for the S&P 500 is still 19x given a 6% decline in earnings next year. That's expensive, particularly when one-year Treasuries pay more than 4%.
If it breaks down, the measured target of the double top is 3750.