Lennar Corp. named Rick Beckwitt as its new chief executive officer, succeeding Stuart Miller, who was appointed executive chairman, as part of several management changes announced by the home builder. Beckwitt has been with Lennar for 12 years, and has been president since 2011. The company has also elected Diane Bessette as the new chief financial officer, succeeding Bruce Gross, who as held the role since 1997. Gross was named the CEO of Lennar Financial Services. Jon Jaffe was named the new president of Lennar, and will continue in his role of chief operating officer. The stock, which was still inactive in premarket trade, has tumbled 16% over the past three months, while the SPDR S&P Homebuilders ETF has lost 12% and the S&P 500 has dropped 5.2%.