"NYSE short interest decreased 6.7% to 12.5 billion shares in the past two weeks from 13.4 billion shares on January 13, the lowest level on record," the research firm noted in its weekly fund flow report on Wednesday. "Historical data shows that short interest is a solid contrarian indicator (decreases are typically bad for equities). Short interest has fallen drastically over the last couple months after hitting a record high of 16.1 billion shares on September 30."

Just another datapoint to ponder. Thursday's strong showing was a big positive for equities though because the major indices hadn't really moved much at all since Feb. 3, a lull that fed the idea that sellers were waiting in the wings. The bears will really be on the run if Greece clears this next hurdle and the data continues to improve.

Apple did its part on Thursday, pushing higher to close at $502.21, up a little less than 1%. It was a good sign after the stock succumbed to a so-called "bearish engulfing" on Wednesday.

As for Friday's scheduled news, K-Swiss ( KSWS) is reporting its fiscal fourth-quarter results before the opening bell, and the average estimate of analysts polled by Thomson Reuters is for a loss of 42 cents a share in the December-ended period on revenue of $41.4 million.

Shares of the Westlake Village, Calif.-based footwear maker have been decimated over the past year, falling more than 60%, as its domestic business has floundered. The company hasn't reported a quarterly profit in more than three years, but the shares have bounced along with the broad market since the calendar turned, rising nearly 26% so far in 2012. At Thursday's regular-session close of $3.75, the stock has surged more than 50% since closing at a 52-week low of $2.47 on Dec. 16.

Sell-side coverage of the stock is sparse with just three analysts holding opinions with ratings split between strong buy, hold and underperform. Sterne Agee is sitting in the middle at hold, and the firm recently upgraded the stock to hold from underperform on Feb. 6, citing valuation but also keeping expectations well in check.

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