Darden Restaurants Inc DRI.N added 4.3% after it announced a new share buyback plan and forecast upbeat fourth-quarter revenue and profit. By Devik Jain March 25 (Reuters) - The technology-heavy Nasdaq led Wall Street lower on Thursday as a rotation out of richly valued stocks into underpriced sectors added to pressure from quarter-end rebalancing by institutional investors. The Nasdaq Composite .IXIC has fallen in March after four straight months of gains as rosy economic projections lifted demand for undervalued cyclical stocks, but also raised fears of higher inflation and a potential tax hike.