Exhibit 99.27 MBNA MASTER CREDIT CARD TRUST II SERIES 1997-M KEY PERFORMANCE FACTORS December 31, 1999 Expected B Maturity 10/15/02 Blended Coupon 6.3501% Excess Protection Level 3 Month Average 5.22% December, 1999 5.02% November, 1999 5.17% October, 1999 5.48% Cash Yield 19.20% Investor Charge Offs 5.04% Base Rate 9.14% Over 30 Day Delinquency 4.63% Seller's Interest 11.35% Total Payment Rate 14.35% Total Principal Balance $49,947,826,881.37 Investor Participation Amount $750,000,000.00 Seller Participation Amount $5,671,007,362.88