Exhibit 99.31 MBNA MASTER CREDIT CARD TRUST II SERIES 1998-D KEY PERFORMANCE FACTORS February 29, 2000 Expected B Maturity 7/15/03 Blended Coupon 5.8627% Excess Protection Level 3 Month Average 5.56% February, 2000 6.31% January, 2000 5.54% December, 1999 4.84% Cash Yield18.80% Investor Charge Offs 4.75% Base Rate 7.74% Over 30 Day Delinquency 5.01% Seller's Interest 9.54% Total Payment Rate14.30% Total Principal Balance$48,263,301,515.80 Investor Participation Amount$559,000,000.00 Seller Participation Amount$4,604,500,997.31