Peter P. Costa, president of Empire Executions, Inc., discusses this week’s economic calendar, including retail sales, CPI and housing starts data.Macy's Inc. (NYSE: M) is scheduled to report quarterly earnings before the market opens on Wednesday, and Wall Street expects the department store to report second quarter earnings of 79 cents per share on revenue of $6.28 billion, according to analysts polled by Reuters.Shares of Macy’s Inc. fell 0.82 percent to $48.12 in afternoon trade.“The retailers have suffered online and you have to see how their online sales are going, because more and more money is gravitating that way,” said Costa. “Macy’s presence online is not as significant as it should be, and I think you have to see what their approach to it’s going to be over the next couple of quarters.”Wal-Mart Stores Inc. (NYSE: WMT) issues earnings results before the bell on Thursday. Analysts forecast the world’s biggest retailer to report second quarter earnings of $1.25 per share on revenue of $118.74 billion, according to a poll conducted by Reuters.“Walmart has a very good presence online, and I think that it’s something you want to keep an eye on,” added Costa.  In mid-day trade, shares of Wal-Mart Stores Inc. rose 0.29 percent to $77.12.Economists will look to retail sales data for the month of July on Tuesday, the Consumer Price Index on Thursday and housing starts on Friday.