The ratings on Buffalo, N.Y.-based M&T Bank Corp. (M&T) are based on its good asset quality, solid operating performance relative to peers', and strong market positions in upstate New York, central Pennsylvania, and the Maryland-northern Virginia-District of Columbia area. These positive factors are tempered by the company's low tangible capital ratios, as acquisitions have resulted in a large amount of goodwill; and its relatively high concentration in commercial real estate (CRE) loans, which Standard&Poor's Ratings Services views as an area of potential vulnerability. M&T's earnings are a positive ratings consideration for the company. Despite some decline due to the economic downturn, the company has remained profitable, and its income has outperformed peers'. Earnings reflect steady levels of noninterest