Exhibit 99.13 MBNA MASTER CREDIT CARD TRUST II SERIES 1996-B KEY PERFORMANCE FACTORS May 31, 1999 Expected B Maturity 4/17/06 Blended Coupon 5.2077% Excess Protection Level 3 Month Average 6.40% May, 1999 7.54% April, 1999 5.02% March, 1999 6.64% Cash Yield 19.45% Investor Charge Offs 4.88% Base Rate 7.03% Over 30 Day Delinquency 4.89% Seller's Interest 6.97% Total Payment Rate 14.69% Total Principal Balance $41,914,776,221.36 Investor Participation Amount $500,000,000.00 Seller Participation Amount $2,922,256,702.87