Just three weeks ago, Federal Reserve Chair Jerome Powell spoke to reporters after the central bank had kept its key interest rate unchanged for a fifth straight meeting and said the job market was “solid.

Wall Street's main indexes were set for a lower open on Thursday, as investors turned cautious ahead of the Federal Reserve's three-day conference in Jackson Hole, while big-box retailer Walmart's quarterly results did little to boost sentiment.

Dollar Tree has underperformed the broader market over the past year, but analysts are moderately optimistic about the stock’s prospects.

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.

For the quarter to July 31, Walmart’s adjusted earnings per share, which excludes nonrecurring items, rose to 68 cents from 67 cents in the same period a year ago, to miss the average analyst EPS estimate compiled by FactSet of 73 cents.