Tuesday Sector Leaders: Energy, Materials

In afternoon trading on Tuesday, Energy stocks are the best performing sector, up 2.0%. Within that group, Southwestern Energy Company (NYSE: SWN) and Pioneer Natural Resources Co (NYSE: PXD) are two of the day's stand-outs, showing a gain of 7.5% and 6.8%, respectively. Among energy ETFs, one ETF following the sector is the Energy Select Sector SPDR ETF (AMEX: XLE), which is up 1.4% on the day, and up 12.24% year-to-date. Southwestern Energy Company, meanwhile, is up 82.98% year-to-date, and Pi...