Base Offering Circular - Multifamily 482090 56 Standard Abbreviation Category of Class Definition XAC Index Allocation Classes whose principal distribution allocations are based on the value of an index. INTEREST TYPES ARB Ascending Rate Classes that have predetermined Interest Rates that increase changes one or more times on dates determined before issuance. DLY Delay Any class, other than a Fixed Rate Class, for which there is a delay between the end of its Accrual Period and the related Distribution Date. DIF Differential Classes with Interest Rates that are equal to the difference between two specified indices. DRB Descending Rate Classes that have predetermined Interest Rates that decrease one or more times on dates determined before issuance. EXE Excess Classes that receive any principal and interest paid on the underlying Ginnie Mae Multifamily Certificates in excess of the amount of the prescribed principal and interest required to be paid on all Classes in the Series. Excess Classes sometimes have specified principal amounts but no specified Interest Rates. FIX Fixed Rate Classes with Interest Rates that are fixed throughout the lives of the Classes. FLT Floating Rate Classes with Interest Rates that are reset periodically based on an index and that vary directly with changes in the index. INV Inverse Floating Rate Classes with Interest Rates that are reset periodically based on an index and that vary inversely with changes in the index. IO Interest Only Classes that receive some or all of the interest payments made on the underlying Ginnie Mae Multifamily Certificates and little or no principal. Interest Only Classes have either a nominal or a notional principal amount. A nominal principal amount represents actual principal that will be paid on the Class. It is referred to as nominal because it is extremely small compared to other Classes. A notional principal amount is the amount used as a reference to calculate the amount of interest due on an Interest Only Class that is not entitled to any principal. NPR No Payment Residual Residual Classes that are designed to receive no distributions of interest. PO Principal Only Classes with a fixed interest rate of zero.