This is what to watch on the last trading day of the first quarter, March 31st. On the earnings docket, consumer electronics retailer Conn's will report before the bell and pet food maker FreshPet after. The S&P Case-Shiller 20-city home price index is expected to show a slight improvement from December. Business activity in the Chicago region is expected to have improved over March in the latest Chicago PMI figures. The Conference Board's consumer confidence index is forecast to recover close to 7-year highs reached earlier this year. Negotiations between six world powers and Iran will reach a deadline in which a preliminary nuclear deal will be agreed upon.