The S&P 500 could be building an S/H/S top, but we need a break below support at 3,384 for a decline to a minimum of 3,818 with is the measured target of the S/H/S top. The measured target is only the minimum objective to expect. The possible decline could easily be much larger and only part of an even larger top-formation.
To invalidate a break above the right shoulder top at 3,931. It may flip the formation target around and call for a rally to at least 3,996
Trading recommendation:
Sell a break below 3,384 for a decline to minimum 3,818 or buy a break above 3,931 for a rally to minimum 3,996.