The Merrill Lynch Puttable FLOATs/RITES Trust puttable floating option tax-exempt receipts series PT-750, relating to District of Columbia GO refunding bonds series 1999B, is rated 'AAA/A-1+'. The long-term component of the rating is based on the FSA-insured underlying bond. The short-term component of the rating is based on a liquidity guarantee from Landesbank Hessen-Thuringen Girozentrale, and the expiration date of the liquidity facility is Feb. 15, 2004.