BY THE NUMBERS

U.S. stock futures fell Friday, marking a key date, Sept. 17, that has historically ushered in a rough patch for the market in an already traditionally tough month. The Dow Jones Industrial Average declined Thursday, though it ended way above session lows. The S&P 500 dipped as well, while the Nasdaq bucked the trend and rose slightly. (CNBC)

Despite the September angst, all three benchmarks were tracking for weekly gains. Ahead of Friday's open, the Dow, S&P 500 and Nasdaq weren't too far from their recent record closes — about 2.5%, 1.4%, and 1.3% away respectively. (CNBC)

Coinciding with seasonal factors stacked against Wall Street, it's also "quadruple witching" Friday, the simultaneous expiration of stock options, index options, stock futures and index futures. The Fed holds its policy meeting next week, leaving investors already on edge this month to read the tea leaves on tapering. (CNBC)

Fed Chairman Jerome Powell has called for a review of the central bank's ethics rules for appropriate financial activities after disclosures that several senior Fed officials held significant investments and others made multimillion-dollar stock trades in 2020. (CNBC)