US markets to follow Fed minutes, Yellen speech By: CNBC.com News May 21, 2014 at 05:13 AM EDT U.S. stock index futures signaled a higher open, despite ongoing concerns about weak earnings and uncertainty regarding global central bank policy. Read More >> Related Stocks: American Eagle Outfitters Lowe's Companies Sentinelone Inc Cl A Staples Target Corp Tiffany & Co