SLM Student Loan Trust 1998-1 Quarterly Servicing Report
Collection Period 04/01/2005 - 06/30/2005 Distribution Date 07/25/2005
I. Deal Parameters
| A | Student Loan Portfolio Characteristics | 03/19/1998 | 03/31/2005 | 06/30/2005 | ||||||||||||
| Principal Balance | $ | 2,949,265,755.00 | $ | 596,957,565.35 | $ | 527,859,131.05 | ||||||||||
| Interest to be Capitalized Balance | 49,895,105.00 | 3,691,058.64 | 3,038,134.24 | |||||||||||||
| Pool Balance | $ | 2,999,160,860.00 | $ | 600,648,623.99 | $ | 530,897,265.29 | ||||||||||
| Specified Reserve Account Balance | 7,497,902.00 | - N/A - | - N/A - | |||||||||||||
| Adjusted Pool (1) | $ | 3,006,658,762.00 | $ | 600,648,623.99 | $ | 530,897,265.29 | ||||||||||
| Weighted Average Coupon (WAC) | 8.23 | % | 5.48 | % | 5.57 | % | ||||||||||
| Weighted Average Remaining Term | 121.00 | 88.53 | 87.60 | |||||||||||||
| Number of Loans | 761,259 | 207,361 | 188,038 | |||||||||||||
| Number of Borrowers | 325,034 | 96,087 | 88,087 | |||||||||||||
| Since Issued CPR | 9.62 | % | 10.01 | % | ||||||||||||
| (1) | The Specified Reserve Account balance is included in the Adjusted Pool until the Pool Balance is less than 40% of the original pool. | |||||||||||||||
| B | Debt Securities | Cusip/Isin | 04/25/2005 | 07/25/2005 | ||||||||||||
| A1 | 78442GAX4 | $ | — | $ | — | |||||||||||
| A2 | 78442GAY2 | $ | 494,098,623.99 | $ | 424,347,265.29 | |||||||||||
| Certs | 78442GAZ9 | $ | 106,550,000.00 | $ | 106,550,000.00 | |||||||||||
| C | Account Balances | 04/25/2005 | 07/25/2005 | |||||||||||||
| Reserve Account Balance | $ | 2,999,161.00 | $ | 2,999,161.00 | ||||||||||||
| D | Asset/Liability | 04/25/2005 | 07/25/2005 | |||||||||||||
| Adjusted Pool Balance | $ | 600,648,623.99 | $ | 530,897,265.29 | ||||||||||||
| Total Notes | $ | 600,648,623.99 | $ | 530,897,265.29 | ||||||||||||
| Difference | $ | — | $ | — | ||||||||||||
| Parity Ratio | 1.00000 | 1.00000 | ||||||||||||||
Page 1 of 8
II. Trust Activity 04/01/2005 through 06/30/2005
| A | Student Loan Principal Receipts | |||||||
| Borrower Principal | 24,263,187.81 | |||||||
| Guarantor Principal | 8,381,397.28 | |||||||
| Consolidation Activity Principal | 39,353,584.20 | |||||||
| Seller Principal Reimbursement | 3,149.33 | |||||||
| Servicer Principal Reimbursement | 2,334.39 | |||||||
| Rejected Claim Repurchased Principal | 3,510.50 | |||||||
| Other Principal Deposits | 3,214.10 | |||||||
| Total Principal Receipts | $ | 72,010,377.61 | ||||||
| B | Student Loan Interest Receipts | |||||||
| Borrower Interest | 4,047,736.83 | |||||||
| Guarantor Interest | 443,279.22 | |||||||
| Consolidation Activity Interest | 340,808.24 | |||||||
| Special Allowance Payments | 1,594,057.25 | |||||||
| Interest Subsidy Payments | 656,245.92 | |||||||
| Seller Interest Reimbursement | 3,629.74 | |||||||
| Servicer Interest Reimbursement | 29,646.12 | |||||||
| Rejected Claim Repurchased Interest | 208.73 | |||||||
| Other Interest Deposits | 375,878.54 | |||||||
| Total Interest Receipts | $ | 7,491,490.59 | ||||||
| C | Investment Income | $ | 418,004.51 | |||||
| D | Funds Borrowed from Next Collection Period | $ | — | |||||
| E | Funds Repaid from Prior Collection Period | $ | — | |||||
| F | Loan Sale or Purchase Proceeds | $ | — | |||||
| G | Initial Deposits to Collection Account | $ | — | |||||
| H | Other Deposits | $ | 273,013.75 | |||||
| I | Less: Funds Previously Remitted: | |||||||
| Servicing Fees | $ | (756,280.56 | ) | |||||
| Consolidation Loan Rebate Fees | $ | (249,244.31 | ) | |||||
Total Funds Previously Remitted | $ | (1,005,524.87 | ) | |||||
| J | AVAILABLE FUNDS | $ | 79,187,361.59 | |||||
| K | Non-Cash Principal Activity During Collection Period | $ | (2,911,943.31 | ) | ||||
| L | Non-Reimbursable Losses During Collection Period | $ | 503.02 | |||||
| M | Aggregate Purchased Amounts by the Depositor, Servicer or Seller | $ | 5,742.26 | |||||
| N | Aggregate Loan Substitutions | $ | — | |||||
Trust 1998-1 Quarterly Servicing Report: Collection Period 04/01/2005-06/30/2005, Distribution Date 07/25/2005
Page 2 of 8
III. 1998-1 Portfolio Characteristics
| 06/30/2005 | 03/31/2005 | |||||||||||||||||||||||||||||||||
| WAC | # Loans | Principal | % of Principal | WAC | # Loans | Principal | % of Principal | |||||||||||||||||||||||||||
| INTERIM: | IN SCHOOL | 3.99 | % | 875 | $ | 2,952,540.90 | 0.559 | % | 3.97 | % | 1,323 | $ | 4,689,100.04 | 0.785 | % | |||||||||||||||||||
| GRACE | 3.97 | % | 428 | $ | 1,512,499.05 | 0.287 | % | 3.90 | % | 375 | $ | 1,356,522.31 | 0.227 | % | ||||||||||||||||||||
| DEFERMENT | 4.89 | % | 21,029 | $ | 72,283,847.33 | 13.694 | % | 4.80 | % | 25,027 | $ | 86,193,860.97 | 14.439 | % | ||||||||||||||||||||
| REPAYMENT: | CURRENT | 5.84 | % | 126,397 | $ | 291,415,445.04 | 55.207 | % | 5.76 | % | 137,045 | $ | 324,409,566.19 | 54.344 | % | |||||||||||||||||||
| 31-60 DAYS DELINQUENT | 5.83 | % | 7,032 | $ | 25,997,889.41 | 4.925 | % | 5.62 | % | 7,209 | $ | 26,868,750.06 | 4.501 | % | ||||||||||||||||||||
| 61-90 DAYS DELINQUENT | 5.79 | % | 4,055 | $ | 16,031,528.32 | 3.037 | % | 5.60 | % | 4,165 | $ | 16,769,506.13 | 2.809 | % | ||||||||||||||||||||
| 91-120 DAYS DELINQUENT | 5.41 | % | 2,446 | $ | 9,654,070.76 | 1.829 | % | 5.54 | % | 2,684 | $ | 11,359,423.29 | 1.903 | % | ||||||||||||||||||||
| > 120 DAYS DELINQUENT | 5.36 | % | 8,257 | $ | 34,227,614.63 | 6.484 | % | 5.36 | % | 8,865 | $ | 36,755,240.25 | 6.157 | % | ||||||||||||||||||||
| FORBEARANCE | 5.28 | % | 16,141 | $ | 68,583,342.11 | 12.993 | % | 5.26 | % | 19,009 | $ | 82,243,770.00 | 13.777 | % | ||||||||||||||||||||
| CLAIMS IN PROCESS | 5.00 | % | 1,365 | $ | 5,144,545.78 | 0.975 | % | 5.05 | % | 1,656 | $ | 6,298,464.33 | 1.055 | % | ||||||||||||||||||||
| AGED CLAIMS REJECTED | 5.53 | % | 13 | $ | 55,807.72 | 0.011 | % | 5.05 | % | 3 | $ | 13,361.78 | 0.002 | % | ||||||||||||||||||||
| TOTAL | 188,038 | $ | 527,859,131.05 | 100.00 | % | 207,361 | $ | 596,957,565.35 | 100.00 | % | ||||||||||||||||||||||||
| * | Percentages may not total 100% due to rounding |
Trust 1998-1 Quarterly Servicing Report: Collection Period 04/01/2005 — 06/30/2005, Distribution Date 07/25/2005
Page 3 of 8
IV. 1998-1 Portfolio Characteristics (cont’d)
| 06/30/2005 | 03/31/2005 | |||||||
| Pool Balance | $ | 530,897,265.29 | $ | 600,648,623.99 | ||||
| Total # Loans | 188,038 | 207,361 | ||||||
| Total # Borrowers | 88,087 | 96,087 | ||||||
| Weighted Average Coupon | 5.57 | % | 5.48 | % | ||||
| Weighted Average Remaining Term | 87.60 | 88.53 | ||||||
| Non-Reimbursable Losses | $ | 503.02 | $ | 6,384.64 | ||||
| Cumulative Non-Reimbursable Losses | $ | 4,647,237.95 | $ | 4,646,734.93 | ||||
| Since Issued CPR | 10.01 | % | 9.62 | % | ||||
| Loan Substitutions | $ | — | $ | — | ||||
| Cumulative Loan Substitutions | $ | — | $ | — | ||||
| Rejected Claim Repurchases | $ | 3,719.23 | $ | 19,987.34 | ||||
| Cumulative Rejected Claim Repurchases | $ | 1,349,559.16 | $ | 1,345,839.93 | ||||
| Unpaid Primary Servicing Fees | $ | — | $ | — | ||||
| Unpaid Administration Fees | $ | — | $ | — | ||||
| Unpaid Carryover Servicing Fees | $ | — | $ | — | ||||
| Note Principal Shortfall | $ | — | $ | — | ||||
| Note Interest Shortfall | $ | — | $ | — | ||||
| Unpaid Interest Carryover | $ | — | $ | — | ||||
Trust 1998-1 Quarterly Servicing Report: Collection Period 04/01/2005 — 06/30/2005, Distribution Date 07/25/2005
Page 4 of 8
V. 1998-1 Portfolio Statistics by School and Program
| A | LOAN TYPE | WAC | # LOANS | $ AMOUNT | % * | |||||||||||||
| - GSL - Subsidized | 4.23 | % | 120,561 | $ | 237,157,071.04 | 44.928 | % | |||||||||||
| - GSL - Unsubsidized | 4.09 | % | 43,262 | 110,479,135.31 | 20.930 | % | ||||||||||||
| - PLUS Loans | 5.27 | % | 4,941 | 11,604,124.81 | 2.198 | % | ||||||||||||
| - SLS Loans | 5.42 | % | 4,043 | 14,267,935.33 | 2.703 | % | ||||||||||||
| - Consolidation Loans | 8.72 | % | 15,231 | 154,350,864.56 | 29.241 | % | ||||||||||||
Total | 5.57 | % | 188,038 | $ | 527,859,131.05 | 100.000 | % | |||||||||||
| B | SCHOOL TYPE | WAC | # LOANS | $ AMOUNT | % * | |||||||||||||
| - Four Year | 4.29 | % | 139,019 | $ | 314,085,122.06 | 59.502 | % | |||||||||||
| - Two Year | 4.17 | % | 25,004 | 43,479,155.94 | 8.237 | % | ||||||||||||
| - Technical | 4.20 | % | 8,820 | 16,256,066.48 | 3.080 | % | ||||||||||||
| - Other | 8.72 | % | 15,195 | 154,038,786.57 | 29.182 | % | ||||||||||||
Total | 5.57 | % | 188,038 | $ | 527,859,131.05 | 100.000 | % | |||||||||||
| C | Student Loan Rate Calculation | |||||||||||||||||
| Borrower Interest Accrued | 6,897,854.83 | |||||||||||||||||
| Interest Subsidy Payments Accrued | $ | 566,981.83 | ||||||||||||||||
| Special Allowance Payments Accrued | $ | 1,716,708.12 | ||||||||||||||||
| Investment Income | $ | 418,004.51 | ||||||||||||||||
| Net Expected Interest Collections | $ | 9,599,549.29 | ||||||||||||||||
| Accrual Daycount Fraction | 0.249315068 | |||||||||||||||||
| Primary Servicing Fee | $ | 1,119,609.96 | ||||||||||||||||
| Admin Fee | $ | 20,000.00 | ||||||||||||||||
| Pool Balance at Beginning of Collection Pd | $ | 600,648,623.99 | ||||||||||||||||
Student Loan Rate | 5.64935 | % | ||||||||||||||||
* Percentages may not total 100% due to rounding.
Trust 1998-1 Quarterly Servicing Report: Collection Period 04/01/2005 — 06/30/2005, Distribution Date 07/25/2005
Page 5 of 8
VI. 1998-1 T-Bill Rates
| Accrual Period | ||||||
| Number of | ||||||
| Start Date | Through | Days Weighted | 91-Day T-Bill | |||
| 04/25/2005 | 04/25/2005 | 1 | 2.864% | |||
| 04/26/2005 | 05/02/2005 | 7 | 2.941% | |||
| 05/03/2005 | 05/09/2005 | 7 | 2.931% | |||
| 05/10/2005 | 05/16/2005 | 7 | 2.911% | |||
| 05/17/2005 | 05/23/2005 | 7 | 2.859% | |||
| 05/24/2005 | 05/31/2005 | 8 | 2.957% | |||
| 06/01/2005 | 06/06/2005 | 6 | 2.998% | |||
| 06/07/2005 | 06/13/2005 | 7 | 3.029% | |||
| 06/14/2005 | 06/20/2005 | 7 | 3.039% | |||
| 06/21/2005 | 06/27/2005 | 7 | 3.029% | |||
| 06/28/2005 | 07/05/2005 | 8 | 3.147% | |||
| 07/06/2005 | 07/11/2005 | 6 | 3.214% | |||
| 07/12/2005 | 07/24/2005 | 13 | 3.204% | |||
Trust 1998-1 Quarterly Servicing Report: Collection Period 04/01/2005 — 06/30/2005, Distribution Date 07/25/2005
Page 6 of 8
VII. 1998-1 Waterfall for Distributions
| Remaining | ||||||||||
| Paid | Funds Balance | |||||||||
| Total Available Funds | $ | 79,187,361.59 | ||||||||
| A | Primary Servicing Fee | $ | 363,329.40 | $ | 78,824,032.19 | |||||
| B | Administration Fee | $ | 20,000.00 | $ | 78,804,032.19 | |||||
| C | Noteholders’ Interest Distribution Amount | $ | 4,669,611.03 | $ | 74,134,421.16 | |||||
| D | Certificateholders’ Return Distribution Amount | $ | 1,062,764.73 | $ | 73,071,656.43 | |||||
| E | Noteholders’ Principal Distribution Amount | $ | 69,751,358.70 | $ | 3,320,297.73 | |||||
| F | Certificateholders’ Balance Distribution Amount | $ | — | $ | 3,320,297.73 | |||||
| G | Reserve Account Reinstatement | $ | — | $ | 3,320,297.73 | |||||
| H | Carryover Servicing Fee | $ | 44,844.00 | $ | 3,275,453.73 | |||||
| I | Noteholders’ Carryover Interest | $ | — | $ | 3,275,453.73 | |||||
| J | Certificateholders’ Carryover Return | $ | — | $ | 3,275,453.73 | |||||
| K | Excess Distribution | $ | 3,275,453.73 | $ | — | |||||
Trust 1998-1 Quarterly Servicing Report: Collection Period 04/01/2005 — 06/30/2005, Distribution Date 07/25/2005
Page 7 of 8
VIII. 1998-1 Distributions
| A | Distribution Amounts | A2 | Certs | |||||||||||
| Cusip/Isin | 78442GAY2 | 78442GAZ9 | ||||||||||||
| Beginning Balance | $ | 494,098,623.99 | $ | 106,550,000.00 | ||||||||||
| Index | TBILL | TBILL | ||||||||||||
| Spread/Fixed Rate | 0.76 | % | 0.97 | % | ||||||||||
| Daycount Fraction | 0.24931507 | 0.24931507 | ||||||||||||
| Interest Rate | 3.79069 | % | 4.00069 | % | ||||||||||
| Accrued Interest Factor | 0.009450767 | 0.009974329 | ||||||||||||
| Current Interest Due | $ | 4,669,611.03 | $ | 1,062,764.73 | ||||||||||
| Interest Shortfall from Prior Period Plus Accrued Interest | $ | — | $ | — | ||||||||||
| Total Interest Due | $ | 4,669,611.03 | $ | 1,062,764.73 | ||||||||||
| Interest Paid | $ | 4,669,611.03 | $ | 1,062,764.73 | ||||||||||
| Interest Shortfall | $ | — | $ | — | ||||||||||
| Carryover Interest Shortfall from Prior Period Plus Accrued Interest | $ | — | $ | — | ||||||||||
| Current Interest Carryover Due | $ | — | $ | — | ||||||||||
| Interest Carryover Paid | $ | — | $ | — | ||||||||||
| Unpaid Interest Carryover | $ | — | $ | — | ||||||||||
| Principal Paid | $ | 69,751,358.70 | $ | — | ||||||||||
| Ending Principal Balance | $ | 424,347,265.29 | $ | 106,550,000.00 | ||||||||||
| Paydown Factor | 0.056963135 | 0.000000000 | ||||||||||||
| Ending Balance Factor | 0.346547379 | 1.000000000 | ||||||||||||
| B | Principal Distribution Reconciliation | |||||||||||||
| Prior Adjusted Pool Balance | $ | 600,648,623.99 | ||||||||||||
| Current Adjusted Pool Balance | $ | 530,897,265.29 | ||||||||||||
| Current Principal Due | $ | 69,751,358.70 | ||||||||||||
| Principal Shortfall from Previous Collection Period | 0.00 | |||||||||||||
| Principal Distribution Amount | $ | 69,751,358.70 | ||||||||||||
| Principal Paid | $ | 69,751,358.70 | ||||||||||||
| Principal Shortfall | $ | — | ||||||||||||
| C | Reserve Account Reconciliation | |||||||||||||
| Beginning Period Balance | $ | 2,999,161.00 | ||||||||||||
| Reserve Funds Utilized | 0.00 | |||||||||||||
| Reserve Funds Reinstated | 0.00 | |||||||||||||
| Excess Distribution Deposit | 3,275,453.73 | |||||||||||||
| Balance Available | $ | 6,274,614.73 | ||||||||||||
| Required Reserve Acct Balance | $ | 2,999,161.00 | ||||||||||||
| Release to Excess Distribution Certificateholder | $ | 3,275,453.73 | ||||||||||||
| Ending Reserve Account Balance | $ | 2,999,161.00 | ||||||||||||
Trust 1998-1 Quarterly Servicing Report: Collection Period 04/01/2005 — 06/30/2005, Distribution Date 07/25/2005
Page 8 of 8
