Exhibit 99.21 MBNA MASTER CREDIT CARD TRUST II SERIES 1996-K KEY PERFORMANCE FACTORS May 31, 1997 Expected B Maturity 11/17/03 Blended Coupon 5.8692% Excess Protection Level 3 Month Average 4.74% May, 1997 4.52% April, 1997 3.81% March, 1997 5.87% Cash Yield 17.28% Investor Charge Offs 4.53% Base Rate 8.23% Over 35 Day Delinquency 4.38% Seller's Interest 15.43% Total Payment Rate 12.75% Total Principal Balance $27,132,480,390.99 Investor Participation Amount $1,000,000,000.00 Seller Participation Amount $4,186,442,872.50