Retail earnings took center stage Thursday, and the signals were sharply mixed. Walmart suffered its biggest drop in years after a rare sales miss, while Ross Stores rallied on strong demand for discounted goods $Wal-Mart(WMT)$-9.2% Walmart is the largest U.S. retailer, selling groceries, household goods, apparel and general merchandise through stores and online. Walmart reported adjusted EPS of $0.81, while revenue came in around $187.9 billion, both above expectations. The weak spot was U.S. comparable sales, which rose just 2.6%, well below the 3.8% analysts expected and the slowest growth in six years. The company still raised its full-year outlook, forecasting sales growth of 4%–5% and adjusted EPS of $2.80–$2.87. But traffic growth slowed, co