U.S. homebuilding dropped to a near two-year low in March, pulled down by persistent weakness in the singlefamily housing segment, suggesting the housing market continued to struggle despite declining mortgage rates.  Some of the weakness in homebuilding likely reflected disruptions caused by massive flooding in the Midwest, with housing starts in the region declining to levels last seen in early 2015. The report bucked a recent tide of upbeat data that indicated the economy regained speed as the first quarter ended.  Housing starts fell 0.3% to a seasonally adjusted annual rate ...