Exhibit 99.42 MBNA MASTER CREDIT CARD TRUST II SERIES 1999-L KEY PERFORMANCE FACTORS September 30, 2000 Expected B Maturity 10/16/2006 Blended Coupon 6.9545% Excess Protection Level 3 Month Average 5.64% September, 2000 5.57% August, 2000 5.42% July, 2000 5.92% Cash Yield19.26% Investor Charge Offs 4.49% Base Rate 9.19% Over 30 Day Delinquency 4.99% Seller's Interest 8.50% Total Payment Rate13.85% Total Principal Balance$54,293,652,263.17 Investor Participation Amount$750,000,000.00 Seller Participation Amount$4,612,451,744.68