In this week's low-volume market, earnings news—just like almost everything else—could have a bigger-than-normal influence on stocks.
Two Dow components—Wal-Mart and Home Depot—report ahead of the opening bell. Home Depot was trading at an all-time high Monday, while Wal-Mart has been a laggard and is 21 percent from its January high.
"Today and Friday were the slowest trading days in two months," said Michael O'Rourke, chief market strategist at JonesTrading. Stocks were boosted by positive home builders sentiment Monday after being whipped earlier when a disappointing Empire State survey fell to its lowest level since 2009. "(Home builders sentiment) was a good number, but there wasn't anything special about it. Empire was terrible."