SLM Student Loan Trust 1999-1 Quarterly Servicing Report ollection Period 07/01/2005-09/30/2005 Distribution Date 10/25/2005 I. Deal Parameters A Student Loan Portfolio haracteristics 06/29/1999 06/30/2005 09/30/2005 Principal Balance $ 978,982,721.00 $ 192,084,257.16 $ 157,054,801.93 Interest to be apitalized Balance 23,093,062.00 1,315,591.44 1,057,555.08 Pool Balance $ 1,002,075,783.00 $ 158,112,357.01 Specified Reserve Account Balance 2,505,189.00 - N/A - - N/A - Adjusted Pool (1) $ 1,004,580,972.00 $ 158,112,357.01 Weighted Average oupon (WA) 7.75% 3.96% Weighted Average Remaining Term 124.00 87.99 86.25 Number of Loans 256,336 74,760 Number of Borrowers 118,086 36,240 31,651 Since Issued PR 15.54% 16.96% (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 usip/isin 07/25/2005 10/25/2005 A1T A1L A2L erts 78442GBD7 78442GBE5 78442GBG0 78442GBH8 $ 157,339,848.60 $ 36,060,00 $ 122,052,357.01 $ 36,060,00 Account Balances 07/25/2005 10/25/2005 Reserve Account Balance D Asset / Liability 07/25/2005 10/25/2005 Adjusted Pool Balance Total Notes Difference Parity Ratio $ 158,112,357.01 $ 158,112,357.01 1.00000 1.00000 Page 1 of 7
II. Trust Activity 07/01/2005 through 09/30/2005 A Student Loan Principal Receipts Borrower Principal 6,498,977.49 Guarantor Principal 2,591,914.26 onsolidation Activity Principal 26,752,279.71 Seller Principal Reimbursement - Servicer Principal Reimbursement 1,164.44 Rejected laim Repurchased Principal - Other Principal Deposits 3,691.55 Total Principal Receipts $ 35,848,027.45 B Student Loan Interest Receipts Borrower Interest Guarantor Interest 1,027,655.18 115,106.45 onsolidation Activity Interest 350,747.70 Special Allowance Payments Interest Subsidy Payments Seller Interest Reimbursement 946,347.20 217,580.83 300.38 Servicer Interest Reimbursement 3,680.20 Rejected laim Repurchased Interest Other Interest Deposits 132,269.27 Total Interest Receipts $ 2,793,687.21 D E F G H I Investment Income Funds Borrowed from Next ollection Period Funds Repaid from Prior ollection Period Loan Sale or Purchase Proceeds Initial Deposits to ollection Account Other Deposits Less: Funds Previously Remitted: Servicing Fees onsolidation Loan Rebate Fees Total Funds Previously Remitted $ 275,856.95 $ 88,203.60 $(273,493.40) $(143.35) $(273,636.75) J K L M AVAILABLE FUNDS Non-ash Principal Activity During ollection Period Non-Reimbursable Losses During ollection Period Aggregate Purchased Amounts by the Depositor, Servicer or Seller $ 38,732,138.46 $(818,572.22) $ 182.57 $ 1,636.66 N Aggregate Loan Substitutions Page 2 of 7 Trust 1999-1 Quarterly Servicing Report: ollection Period 07/01/2005-09/30/2005, Distribution Date 10/25/2005
III. 1999-1 Portfolio haracteristics 09/30/2005 06/30/2005 WA # Loans Principal % of Principal WA # Loans Principal % of Principal INTERIM: IN SHOOL 5.32% 614 $2,243,917.64 1.429% 3.46% 793 $3,076,090.52 1.601% GRAE 5.12% 449 $1,726,618.22 1.099% 3.10% 483 $1,815,230.76 0.945% DEFERMENT 5.36% 8,301 $24,670,705.38 15.708% 3.48% 9,509 $30,351,311.13 15.801% REPAYMENT: URRENT 5.97% 40,882 $80,842,809.78 51.474% 4.09% 48,126 $101,097,574.16 52.632% 31-60 DAYS DELINQUENT 5.96% 2,631 $6,925,505.92 4.410% 4.10% 2,663 $7,674,251.76 3.995% 61-90 DAYS DELINQUENT 5.95% 1,440 $4,295,794.18 2.735% 4.07% 1,545 $4,909,296.43 2.556% 91-120 DAYS DELINQUENT 5.96% 1,069 $3,335,306.84 2.124% 4.11% 1,058 $3,387,663.63 1.764% > 120 DAYS DELINQUENT 5.96% 2,990 $9,970,747.34 6.349% 4.08% 3,269 $10,902,335.89 5.676% FORBEARANE 5.91% 5,842 $21,526,353.06 13.706% 4.05% 6,828 $27,356,350.97 14.242% LAIMS IN PROESS 5.97% 440 $1,517,043.57 0.966% 4.00% 486 $1,514,151.91 0.788% TOTAL $157,054,801.93 10% 74,760 $192,084,257.16 10% * Percentages may not total 100% due to rounding Page 3 of 7 Trust 1999-1 Quarterly Servicing Report: ollection Period 07/01/2005-09/30/2005, Distribution Date 10/25/2005
IV. 1999-1 Portfolio haracteristics (cont'd) 09/30/2005 06/30/2005 Pool Balance Total # Loans Total # Borrowers Weighted Average oupon Weighted Average Remaining Term Non-Reimbursable Losses umulative Non-Reimbursable Losses Since Issued PR Loan Substitutions umulative Loan Substitutions Rejected laim Repurchases umulative Rejected laim Repurchases Unpaid Primary Servicing Fees Unpaid Administration Fees Unpaid arryover Servicing Fees Note Principal Shortfall Note Interest Shortfall Unpaid Interest arryover $158,112,357.01 31,651 86.25 $182.57 $1,108,089.92 16.96% $304,826.72 $193,399,848.60 74,760 36,240 3.96% 87.99 $74.01 $1,107,907.35 15.54% $14,207.14 $304,826.72 Page 4 of 7 Trust 1999-1 Quarterly Servicing Report: ollection Period 07/01/2005-09/30/2005, Distribution Date 10/25/2005
V. 1999-1 Portfolio Statistics by School and Program A LOAN TYPE WA # LOANS $ AMOUNT % * - GSL - Subsidized 5.83% 40,960 $ 89,153,910.38 56.766% - GSL - Unsubsidized 5.74% 18,884 54,071,035.41 34.428% - PLUS Loans 6.29% 3,904 11,671,260.21 7.431% - SLS Loans 6.67% 908 2,103,832.71 1.340% - onsolidation Loans 7.00% 2 54,763.22 0.035% Total $ 157,054,801.93 100% B SHOOL TYPE WA # LOANS $ AMOUNT % * - Four Year 52,419 $ 134,596,954.95 85.701% - Two Year 5.85% 8,514 15,560,656.62 9.908% - Technical 5.89% 3,723 6,842,427.14 4.357% - Other 7.00% 2 54,763.22 0.035% Total $ 157,054,801.93 100% Student Loan Rate alculation Borrower Interest Accrued Interest Subsidy Payments Accrued Special Allowance Payments Accrued Investment Income Net Expected Interest ollections Accrual Daycount Fraction Primary Servicing Fee Admin Fee Pool Balance at Beginning of ollection Pd Student Loan Rate 2,151,607.95 $ 255,222.70 $ 223,471.61 $ 275,856.95 $ 2,906,159.21 0.255555556 $ 396,605.21 $ 20,00 5.03709% *Percentages may not total 100% due to rounding. Page 5 of 7 Trust 1999-1 Quarterly Servicing Report: ollection Period 07/01/2005-09/30/2005, Distribution Date 10/25/2005
VI. 1999-1 Waterfall for Distributions Paid Remaining Funds Balance Total Available Funds $ 38,732,138.46 A Primary Servicing Fee $ 123,111.81 $ 38,609,026.65 B Administration Fee $ 20,00 $ 38,589,026.65 Noteholders' Interest Distribution Amount $ 1,540,007.47 $ 37,049,019.18 D ertificateholders' Return Distribution Amount $ 377,828.67 $ 36,671,190.51 E Noteholders' Principal Distribution Amount $ 35,287,491.59 $ 1,383,698.92 F ertificateholders' Balance Distribution Amount $ 1,383,698.92 G Reserve Account Reinstatement $ 1,383,698.92 H arryover Servicing Fee $ 1,383,698.92 I Noteholders' arryover Interest $ 1,383,698.92 J ertificateholders' arryover Return $ 1,383,698.92 K Excess Distribution $ 1,383,698.92 Page 6 of 7 Trust 1999-1 Quarterly Servicing Report: ollection Period 07/01/2005-09/30/2005, Distribution Date 10/25/2005
VII. 1999-1 Distributions A Distribution Amounts A2L erts usip/isin 78442GBG0 78442GBH8 Beginning Balance $157,339,848.60 $36,060,00 Index LIBOR LIBOR Spread/Fixed Rate 0.18% 0.45% Daycount Fraction 0.25555556 0.25555556 Interest Rate 3.83000% 4.10000% Accrued Interest Factor 9787778 0.010477778 urrent Interest Due $1,540,007.47 $377,828.67 Interest Shortfall from Prior Period Plus Accrued Interest Total Interest Due $1,540,007.47 $377,828.67 Interest Paid $1,540,007.47 $377,828.67 Interest Shortfall arryover Interest Shortfall from Prior Period Plus Accrued Interest urrent Interest arryover Due Interest arryover Paid Unpaid Interest arryover Principal Paid $35,287,491.59 Ending Principal Balance $122,052,357.01 $36,060,00 Paydown Factor 0.081772974 0000000 Ending Balance Factor 0.282836320 1.000000000 B Principal Distribution Reconciliation Prior Adjusted Pool Balance urrent Adjusted Pool Balance urrent Principal Due Principal Shortfall from Previous ollection Period Principal Distribution Amount Principal Paid Principal Shortfall $ 158,112,357.01 $ 35,287,491.59 $ 35,287,491.59 $ 35,287,491.59 Reserve Account Reconciliation Beginning Period Balance Reserve Funds Utilized Reserve Funds Reinstated Excess Distribution Deposit Balance Available Required Reserve Acct Balance Release to Excess Distribution ertificateholder Ending Reserve Account Balance 1,383,698.92 $ 2,385,774.92 $ 1,383,698.92 Page 7 of 7 Trust 1999-1 Quarterly Servicing Report: ollection Period 07/01/2005-09/30/2005, Distribution Date 10/25/2005