"I do not draw the lines. ... The lines draw themselves. It bounces perfectly, perfectly, perfectly, and guess where we're fading just now? Right off the top" of the channel, he said.
"At a minimum, I think we go to the bottom of the channel, which implies about a 5 percent drop. Short the SPY."
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Options trader Mike Khouw is similarly bearish, noting that the S&P's valuation has crept higher.
"The S&P is trading about 17.7 times earnings, that's about a turn and a half richer than it has historically, about 16.2 times," Khouw said Friday.
"At the very least, you'd expect that the multiple would revert back to the mean, that's about an 8.5 percent decline from where the S&P traded today. And only off 3.5 percent from the highs, it's not a big stretch to think that we could see it fall another 8.5 percent here."
To take advantage of such a move, Khouw would advocate buying the S&P 500 ETF March quarterly 200/185 put spread for $3.80. This trade will make money if the SPY is below $196.20 at the end of March, or 2.2 percent below Monday's opening price.