Exhibit 99.13 MBNA MASTER CREDIT CARD TRUST II SERIES 1996-B KEY PERFORMANCE FACTORS April 30, 1999 Expected B Maturity 4/17/06 Blended Coupon 5.2315% Excess Protection Level 3 Month Average 5.88% April, 1999 5.02% March, 1999 6.64% February, 1999 5.98% Cash Yield 17.83% Investor Charge Offs 5.23% Base Rate 7.58% Over 35 Day Delinquency 4.87% Seller's Interest 10.40% Total Payment Rate 14.17% Total Principal Balance $42,469,994,217.25 Investor Participation Amount $500,000,000.00 Seller Participation Amount $4,418,074,698.76