Exhibit 99.21 MBNA MASTER CREDIT CARD TRUST II SERIES 1996-K KEY PERFORMANCE FACTORS August 31, 1997 Expected B Maturity 11/17/03 Blended Coupon 5.8335% Excess Protection Level 3 Month Average 4.68% August, 1997 4.62% July, 1997 4.55% June, 1997 4.86% Cash Yield 17.46% Investor Charge Offs 4.84% Base Rate 8.00% Over 35 Day Delinquency 4.66% Seller's Interest 14.91% Total Payment Rate 12.37% Total Principal Balance $30,603,901,306.35 Investor Participation Amount $1,000,000,000.00 Seller Participation Amount $4,563,766,787.86