Exhibit 99.24 MBNA MASTER CREDIT CARD TRUST II SERIES 1997-B KEY PERFORMANCE FACTORS May 31, 1997 Expected B Maturity 3/15/12 Blended Coupon 5.9210% Excess Protection Level 3 Month Average 3.95% May, 1997 4.43% April, 1997 3.47% March, 1997 N/A Cash Yield 17.28% Investor Charge Offs 4.53% Base Rate 8.32% 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