Costco Wholesale Corp (NASDAQ:COST) has been outperforming on the charts, recently hitting a Sept. 13 record high of $923.82, though the $920 region appears to now be emerging as pressure. Today, COST was last seen up 1.3% at $918.59, looking to add to its 39% year-to-date gain.The discount retail giant is gearing up for its latest earnings report, due out after the close on Thursday, Sept. 26. The stock finished the session lower following its past two reports this year, and after four total in the last tw ...