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When setting up a rule to follow Accelerated Market Discount and PAC method (For example, set the Yield Type field to Net Present Value, and set the Adjustment Type field to PAC), you must set up individual accretion instances for Amortization/Accretion Election (tag 3933) for Market Discount (MD) and Market Premium(MP).
For more information see Recognition of Income Examples Recognition of Paydown Loss/Recovery ExamplesRecognition of Income Examples