## Examples of *Class B-1 Optimal Principal Amount* in a sentence

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**Class B-1 Optimal Principal Amount**.................................................................

Class B-1 Optimal Principal Amount. As to any Distribution Date, an amount equal to the sum of (I) the sum, as to each Outstanding Mortgage Loan, of the product of (x) the Non-PO Fraction with respect to such Mortgage Loan and (y) the sum of:

Class B-1 Optimal Principal Amount. As to any Distribution Date and each Outstanding Mortgage Loan, an amount equal to the sum of

Class B-1 Optimal Principal Amount. As to any Distribution Date, an amount equal to the sum of (I) the sum, as to each Outstanding Mortgage Loan, of:

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**Class B-1 Optimal Principal Amount**.................................................................

Class B-1 Optimal Principal Amount. As to any Distribution Date, an amount equal to the sum, as to each Outstanding Mortgage Loan and, with respect to clause (y)(ii), each Mortgage Loan as to which there has been a Recovery during the Applicable Unscheduled Principal Receipt Period, of the product of (x) the Non-PO Fraction with respect to such Mortgage Loan and (y) the sum of:

Class B-1 Optimal Principal Amount. As to any Distribution Date, an amount equal to the sum, as to each Outstanding Mortgage Loan, of the product of (x) the Non-PO Fraction with respect to such Mortgage Loan and (y) the sum of: (i) the Class B-1 Percentage of (A) the principal portion of the Monthly Payment due on the Due Date occurring in the month of such Distribution Date on such Mortgage Loan, less (B) if the Bankruptcy Loss Amount has been reduced to zero, the principal portion of any Debt Service Reduction with respect to such Mortgage Loan; (ii) the Class B-1 Prepayment Percentage of all Unscheduled Principal Receipts that were received by a Servicer with respect to such Mortgage Loan during the Applicable Unscheduled Principal Receipt Period relating to such Distribution Date for each applicable type of Unscheduled Principal Receipt; (iii) the Class B-1 Prepayment Percentage of the Scheduled Principal Balance of such Mortgage Loan which, during the month preceding the month of such Distribution Date, was repurchased by the Seller pursuant to Section 2.02 or 2.03; and (iv) the Class B-1 Percentage of the excess of the unpaid principal balance of such Mortgage Loan substituted for a defective Mortgage Loan during the month preceding the month in which such Distribution Date occurs over the unpaid principal balance of such defective Mortgage Loan, less the amount allocable to the principal portion of any unreimbursed Periodic Advances previously made by the applicable Servicer, the Master Servicer or the Trustee in respect of such defective Mortgage Loan; provided, however, that if an Optimal Adjustment Event occurs with respect to such Class and such Distribution Date, the Class B-1 Optimal Principal Amount will equal the lesser of (A) the Class B-1 Optimal Principal Amount calculated as described in the preceding provisions and (B) the Adjusted Principal Balance for the Class B-1 Certificates.

Class B-2 Optimal Principal Amount As to any Distribution Date, an amount equal to the sum of (I) the sum, as to each Outstanding Mortgage Loan, of the product of (x) the Non-PO Fraction with respect to such Mortgage Loan and (y) the sum of:

Class B-5 Optimal Principal Amount As to any Distribution Date, an amount equal to the sum of (I) the sum, as to each Outstanding Mortgage Loan, of the product of (x) the Non-PO Fraction with respect to such Mortgage Loan and (y) the sum of:

Class B-6 Optimal Principal Amount As to any Distribution Date, an amount equal to the sum of (I) the sum, as to each Outstanding Mortgage Loan, of the product of (x) the Non-PO Fraction with respect to such Mortgage Loan and (y) the sum of:

Class B-4 Optimal Principal Amount As to any Distribution Date, an amount equal to the sum of (I) the sum, as to each Outstanding Mortgage Loan, of the product of (x) the Non-PO Fraction with respect to such Mortgage Loan and (y) the sum of:

Class B-3 Optimal Principal Amount As to any Distribution Date, an amount equal to the sum of (I) the sum, as to each Outstanding Mortgage Loan, of the product of (x) the Non-PO Fraction with respect to such Mortgage Loan and (y) the sum of:

Class A-PO Optimal Principal Amount As to any Distribution Date, an amount equal to the sum of (I) the sum as to each Outstanding Mortgage Loan, of the product of (x) the PO Fraction with respect to such Mortgage Loan and (y) the sum of:

Class A Non-PO Optimal Principal Amount As to any Distribution Date, an amount equal to the sum, as to each Outstanding Mortgage Loan, of the product of (x) the Non-PO Fraction with respect to such Mortgage Loan, and (y) the sum of:

Senior Optimal Principal Amount For any Distribution Date and any Loan Group, the sum for all Mortgage Loans in such Loan Group of (i) the Senior Percentage of (a) the principal portion of each Scheduled Payment (without giving effect, prior to the Bankruptcy Coverage Termination Date, to any reductions thereof caused by any Debt Service Reductions or Deficient Valuations) due on each such Mortgage Loan on the related Due Date, (b) the principal portion of the Purchase Price of each such Mortgage Loan to the extent it was repurchased by the Transferor pursuant to this Agreement as of such Distribution Date, (c) the Substitution Adjustment Amount in connection with any Deleted Mortgage Loan related to such Loan received with respect to such Distribution Date and (d) any Liquidation Proceeds (including Insurance Proceeds) allocable to recoveries of principal of any Mortgage Loan related to such Loan Group that is not yet a Liquidated Loan, received during the calendar month preceding the month of such Distribution Date, (ii) with respect to each such Mortgage Loan in such Loan Group that became a Liquidated Loan during the calendar month preceding the month of such Distribution Date, the lesser of (a) the Senior Percentage of the Scheduled Principal Balance of such Mortgage Loan, and (b) either (A) the Senior Prepayment Percentage, or (B) if an Excess Loss was sustained with respect to such Liquidated Loan during such prior calendar month, the Senior Percentage of the amount of the Liquidation Proceeds allocable to principal received with respect to such Mortgage Loan, (iii) the Senior Prepayment Percentage of the sum of (a) all Principal Prepayments in Full of Mortgage Loans in such Loan Group received during the related Prepayment Period and (b) all partial Principal Prepayments of Mortgage Loans in such Loan Group and applied during the related Prepayment Period and (iv) with respect to any Distribution Date prior to the Cross-Over Date only, the Senior Prepayment Percentage of the Recoveries for such Loan Group received during the related Prepayment Period; provided, however, that, if a Bankruptcy Loss that is an Excess Loss is sustained with respect to such Mortgage Loan that is not a Liquidated Loan, the Senior Optimal Principal Amount will be reduced on the related Distribution Date by the Senior Percentage of the principal portion of such Bankruptcy Loss.

Class P Principal Amount As of the Closing Date, $100.

PO Principal Amount As to any Distribution Date and Loan Group, the sum of the applicable PO Percentage of (a) the principal portion of each Monthly Payment due on each Mortgage Loan in such Loan Group on the related Due Date, (b) the Stated Principal Balance, as of the date of repurchase, of each Mortgage Loan in such Loan Group that was repurchased by the Depositor pursuant to this Agreement as of such Distribution Date, (c) any Substitution Adjustment Amount in connection with any Defective Mortgage Loan in such Loan Group received with respect to such Distribution Date, (d) any Liquidation Proceeds allocable to recoveries of principal of Mortgage Loans in such Loan Group that are not yet Liquidated Mortgage Loans received during the calendar month preceding the month of such Distribution Date, (e) with respect to each Mortgage Loan in such Loan Group that became a Liquidated Mortgage Loan during the calendar month preceding the month of such Distribution Date, the amount of Liquidation Proceeds (excluding Excess Proceeds) allocable to principal received with respect to such Mortgage Loan during the calendar month preceding the month of such Distribution Date with respect to such Mortgage Loan and (f) all Principal Prepayments received on the Mortgage Loans in such Loan Group received during the calendar month preceding the month of such Distribution Date.

Class Principal Amount With respect to each Class of Certificates, the aggregate of the Certificate Principal Amounts of all Certificates of such Class at the date of determination. With respect to any Lower-Tier Interest, the initial Class Principal Amount as shown or described in the table set forth in the Preliminary Statement for the issuing REMIC, as reduced by principal distributed with respect to such Lower-Tier Interest and Realized Losses allocated to such Lower-Tier Interest at the date of determination.

Subordinated Optimal Principal Amount With respect to each Mortgage Pool and each Distribution Date, an amount equal to the sum of the following (but in no event greater than the aggregate Class Certificate Balances of the Subordinated Certificates immediately prior to such Distribution Date):

Non-PO Principal Amount As to any Distribution Date and Loan Group, the sum of (i) the sum of the applicable Non-PO Percentage of (a) the principal portion of each Monthly Payment due on each Mortgage Loan in such Loan Group on the related Due Date, (b) the Stated Principal Balance, as of the date of repurchase, of each Mortgage Loan in such Loan Group that was repurchased by the Depositor pursuant to this Agreement as of such Distribution Date, (c) any Substitution Adjustment Amount in connection with a Defective Mortgage Loan in such Loan Group received with respect to such Distribution Date, (d) any Liquidation Proceeds allocable to recoveries of principal of Mortgage Loans in such Loan Group that are not yet Liquidated Mortgage Loans received during the calendar month preceding the month of such Distribution Date, (e) with respect to each Mortgage Loan in such Loan Group that became a Liquidated Mortgage Loan during the calendar month preceding the month of such Distribution Date, the amount of Liquidation Proceeds (excluding Excess Proceeds) allocable to principal received with respect to such Mortgage Loan during the calendar month preceding the month of such Distribution Date and (f) all Principal Prepayments on the Mortgage Loans in such Loan Group received during the calendar month preceding the month of such Distribution Date; and (ii) the Non-PO Recovery for such Distribution Date.

Initial Principal Amount means, with respect to any Series or Class (or Subclass) of Notes, the aggregate initial principal amount of such Series or Class (or Subclass) of Notes specified in the applicable Series Supplement.

Current Principal Amount With respect to any Certificate as of any Distribution Date, the initial principal amount of such Certificate, and reduced by (i) all amounts distributed on previous Distribution Dates on such Certificate with respect to principal, (ii) the principal portion of all Realized Losses allocated prior to such Distribution Date to such Certificate, taking account of the Loss Allocation Limitation and (iii) in the case of a Subordinate Certificate, such Certificate's pro rata share, if any, of the applicable Subordinate Certificate Writedown Amount for previous Distribution Dates. With respect to any Class of Certificates, the Current Principal Amount thereof will equal the sum of the Current Principal Amounts of all Certificates in such Class. Notwithstanding the foregoing, solely for purposes of giving consents, directions, waivers, approvals, requests and notices, the Class R-I and Class R-II Certificates after the Distribution Date on which they each receive the distribution of the last dollar of their respective original principal amount shall be deemed to have Current Principal Amounts equal to their respective Current Principal Amounts on the day immediately preceding such Distribution Date.

Notional Principal Amount For calculating interest payments, on each Class of outstanding Interest Only MAC Notes as of any Payment Date, an amount equal to the outstanding Class Principal Balance as of such Payment Date of the portion of the related Class of Class M Notes that was exchanged for such Interest Only MAC Note.

Original Principal Amount means $270,000,000 for the Class A-1 Notes, $200,000,000 for the Class A-2a Notes, $290,000,000 for the Class A-2b Notes, $410,000,000 for the Class A-3 Notes and $132,710,000 for the Class A-4 Notes.

Subordinate Optimal Principal Amount For any Distribution Date and any Loan Group, the sum for each Mortgage Loan in such Loan Group of (i) the Subordinate Percentage of (a) the principal portion of each Scheduled Payment (without giving effect, prior to the Bankruptcy Coverage Termination Date, to any reductions thereof caused by any Debt Service Reductions or Deficient Valuations) due on each such Mortgage Loan on the related Due Date, (b) the principal portion of the Purchase Price of each such Mortgage Loan to the extent it was repurchased by the Transferor pursuant to this Agreement as of such Distribution Date, (c) the Substitution Adjustment Amount in connection with any Deleted Mortgage Loan related to such Loan Group received with respect to such Distribution Date, (d) any Liquidation Proceeds (including Insurance Proceeds) allocable to recoveries of principal of Mortgage Loans related to such Loan Group that are not yet Liquidated Loans, received during the calendar month preceding the month of such Distribution Date, (ii) with respect to each Mortgage Loan in such Loan Group that became a Liquidated Loan during the calendar month preceding the month of such Distribution Date, the portion of the amount of the Liquidation Proceeds allocable to principal received with respect to such Mortgage Loan that was not included in clause (ii) of the definition of "Senior Optimal Principal Amount" for such Distribution Date, (iii) the Subordinate Prepayment Percentage of the sum of (a) all Principal Prepayments in Full of Mortgage Loans in such Loan Group received during the related Prepayment Period and (b) all partial Principal Prepayments of Mortgage Loans in such Loan Group and applied during the related Prepayment Period and (iv) with respect to any Distribution Date prior to the Cross-Over Date only, the Subordinate Prepayment Percentage related to such Group of the Recoveries received during the related Prepayment Period; provided, however, that if a Bankruptcy Loss that is an Excess Loss is sustained with respect to a Mortgage Loan in such Loan Group that is not a Liquidated Loan, the Subordinate Optimal Principal Amount will be reduced on the related Distribution Date by the Subordinate Percentage of the principal portion of such Bankruptcy Loss.

PO Formula Principal Amount As to any Distribution Date, the sum of the applicable PO Percentage of (a) the principal portion of each Scheduled Payment (without giving effect, prior to the Bankruptcy Coverage Termination Date, to any reductions thereof caused by any Debt Service Reductions or Deficient Valuations) due on each Mortgage Loan on the related Due Date, (b) the Stated Principal Balance of each Mortgage Loan that was repurchased by the Seller or the Master Servicer pursuant to this Agreement as of such Distribution Date, (c) the Substitution Adjustment Amount in connection with any Deleted Mortgage Loan received with respect to such Distribution Date, (d) any Insurance Proceeds or Liquidation Proceeds allocable to recoveries of principal of Mortgage Loans that are not yet Liquidated Mortgage Loans received during the calendar month preceding the month of such Distribution Date, (e) with respect to each Mortgage Loan that became a Liquidated Mortgage Loan during the month preceding the calendar month of such Distribution Date, the amount of Liquidation Proceeds allocable to principal received during the month preceding the month of such Distribution Date with respect to such Mortgage Loan and (f) all Principal Prepayments received during the related Prepayment Period.

Lower-Tier Principal Amount As described in the Preliminary Statement.

Initial Dollar Principal Amount means $1,000,000,000, or such higher amount as is specified in any Notice of Additional Issuance under Section 2.09 hereof.

Class A Non-PO Optimal Amount As to any Distribution Date, the sum for such Distribution Date of (i) the Class A Interest Accrual Amount, (ii) the Aggregate Class A Unpaid Interest Shortfall and (iii) the Class A Non-PO Optimal Principal Amount.

Non-PO Formula Principal Amount As to any Distribution Date, the sum of (i) the sum of the applicable Non-PO Percentage of (a) all monthly payments of principal due on each Mortgage Loan on the related Due Date, (b) the principal portion of the purchase price of each Mortgage Loan that was repurchased by the Seller pursuant to this Agreement as of such Distribution Date, excluding any Mortgage Loan that was repurchased due to a modification of the Mortgage Rate, (c) the Substitution Adjustment Amount in connection with any Deleted Mortgage Loan received with respect to such Distribution Date, (d) any Insurance Proceeds or Liquidation Proceeds allocable to recoveries of principal of Mortgage Loans that are not yet Liquidated Mortgage Loans received during the calendar month preceding the month of such Distribution Date, (e) with respect to each Mortgage Loan that became a Liquidated Mortgage Loan during the calendar month preceding the month of such Distribution Date, the amount of Liquidation Proceeds allocable to principal received with respect to such Mortgage Loan, and (f) all partial and full Principal Prepayments received during the related Prepayment Period and (ii) (A) any Subsequent Recoveries received during the calendar month preceding the month of such Distribution Date, or (B) with respect to Subsequent Recoveries attributable to a Discount Mortgage Loan that incurred (1) an Excess Loss or (2) a Realized Loss after the Senior Credit Support Depletion Date, the Non-PO Percentage of any Subsequent Recoveries received during the calendar month preceding the month of such Distribution Date.

Applicable Principal Amount means either (i) if the Tax Event Redemption Date occurs prior to February 16, 2001, the aggregate principal amount of the Debentures corresponding to the aggregate stated liquidation amount of the Preferred Securities which are components of Income PRIDES on the Tax Event Redemption Date or (ii) if the Tax Event Redemption occurs on or after February 16, 2001, the aggregate principal amount of the Debentures corresponding to the aggregate stated liquidation amount of the Preferred Securities outstanding on such Tax Event Redemption Date.

Original Class B-1 Principal Balance The Class B-1 Principal Balance as of the Cut-Off Date, as set forth in Section 11.15.