Shares of Walmart Inc. dropped in early trading Thursday, after the discount-retail behemoth missed fiscal second-quarter profit expectations, but raised its full-year outlook and saw strength in sales at both its retail and Sam’s Club warehouse stores.

The $100 level acted as support earlier in August. But since February, $100 has been a pretty strong resistance level. Now that WMT stock is below it once more, it is a worrying sign. Shares of Walmart rarely go on sale unless the market perceives a macro shock.

U.S. stocks are falling again, this time after the country’s largest retailer reported profits that came up short of Wall Street’s expectations. The S&P 500 fell 0.5% in early trading Thursday and was on track for a fifth straight modest loss since setting an all-time high last week.