Gap Inc. GPS, -0.85% is leaving the S&P 500 index SPX, -0.15%, index provider S&P Dow Jones Indices said late Wednesday, underscoring the challenges faced by retailers in recent years. Constellation Energy Corp. CEG, +50.00% will replace Gap in the key equity index, with the retailer, parent to Banana Republic, Old Navy and Athleta in addition to the namesake store brand and others, replacing fast-food chain Jack in the Box Inc. JACK, +0.47% in the S&P MidCap 400. Jack in the Box will replace Spectrum Pharmaceuticals Inc. SPPI, -4.40% in the S&P SmallCap 600, S&P Dow Jones said. The changes take effect on Feb. 3. Exelon Corp. EXC, +0.43% is spinning off Constellation Energy in a transaction expected to close Feb. 2.
