S&P 500's Recent Flat Close Hides a Brutal Split Underneath

The S&P 500 closed Thursday down just two points, a session so quiet it barely registered on a chart.

But scroll past the index level and the picture turns ugly: 328 of its member stocks fell while only 174 rose, meaning the “flat” close was actually a broad retreat papered over by a handful of winners.

A Market Held Up By a Few Names

The gap between the headline number and the internals…