Exhibit 99.40 MBNA MASTER CREDIT CARD TRUST II SERIES 1998-J KEY PERFORMANCE FACTORS January 31, 1999 Expected B Maturity 9/15/03 Blended Coupon 5.3342% Excess Protection Level 3 Month Average 5.52% January, 1999 5.94% December, 1998 6.36% November, 1998 4.26% Cash Yield18.21% Investor Charge Offs 4.95% Base Rate 7.32% Over 35 Day Delinquency 5.29% Seller's Interest 8.19% Total Payment Rate14.12% Total Principal Balance$40,086,865,639.98 Investor Participation Amount$750,000,000.00 Seller Participation Amount$3,284,946,121.49