# SQL Server PMT function

PMT

Updated: 5 August 2010
Use PMT to calculate the periodic payment for an annuity.
Syntax
SELECT [westclintech].[wct].[PMT] (
<@Rate, float,>
,<@Nper, float,>
,<@PV, float,>
,<@FV, float,>
,<@Pay_type, int,>)

Arguments
@Rate
the interest rate per period. @Rate is an expression of type float or of a type that can be implicitly converted to float.
@Nper
the total number of periods in the annuity to be calculated. @Nper is an expression of type float or of a type that can be implicitly converted to float.
@PV
the present value of the future payments . @PV is an expression of type float or of a type that can be implicitly converted to float.
@FV
the future value at the end of the annuity. @FV is an expression of type float or of a type that can be implicitly converted to float.
@Pay_type
the number 0 or 1 and indicates when payments are due. @Pay_type is an expression of type int or of a type that can be implicitly converted to int. If @Pay_type is NULL it is assumed to be 0.
 Set @Pay_type equal to If payments are due 0 At the end of a period 1 At the beginning of a period

Return Type
float
Remarks
Â·         If @Pay_type is equal to 0, PMT is calculated as
PMT = (@PV+((@PV+@FV)/(((1+@Rate)^@Nper)-1)))*@Rate
Â·         If @Pay_type is equal to 1, PMT is calculated as
PMT = (@PV+((@PV+@FV)/(((1+@Rate)^@Nper)-1)))*(@Rate/(1+@rate))
Â·         It is important to be consistent with the units for @Rate and @Nper. For example if payments are to be paid monthly, then @Rate should be the monthly rate, which can be specified as the annual rate divided by 12. If payments are made quarterly, divide the annual rate by 4. If payments are made semi-annually, divide the annual rate by 2.
Example

SELECT wct.PMT(.06/12,
12*20
,-400000
,100000
,1)
Here is the result set
----------------------
2636.11261237266