FV Function (Future value) - SQL Server

FV.sql

/** 
 * Future Value (FV)
 * (SQL Server)
 * AzsaturnDx (2020) - No copyright at all
 *
 * Calculates the future value of an investment based on a constant interest rate. You can use FV with either periodic, constant payments, or a single lump sum payment.
 *
 * @Rate FLOAT - Required. The interest rate for the loan.
 * @Periods INT - Required. The total number of payments for the loan.
 * @Payment FLOAT - Required. The payment made each period; it cannot change over the life of the annuity.
 * @Value FLOAT - Optional. The present value, or the lump-sum amount that a series of future payments is worth right now. If pv is omitted, it is assumed to be 0 (zero), and you must include the pmt argument.
 * @Type INT - Optional. The number 0 (zero) or 1 and indicates when payments are due. (0 = End of Period , 1 = Start of Period)
 * @return FLOAT Future Value
 *
 * @Example
 * 	  SELECT dbo.FV(.20,12,1,2,0)
 *
 * More financial functions are available @: https://gist.github.com/Azsaturndx/8ce3e47e2d3210a65fc83b09ac32da5f
 */


CREATE FUNCTION [dbo].[FV]
	(@Rate FLOAT
	,@Periods INT
	,@Payment FLOAT
	,@Value FLOAT
	,@Type INT)  
RETURNS FLOAT
    BEGIN   
	    SET @Type = ISNULL(@Type,0);
		SET @Value = ISNULL(@Value,0);
		DECLARE @Result AS FLOAT=0;
		DECLARE @Term AS FLOAT = 0;

		IF @Rate=0
		BEGIN
			SET @Result=(@Value+@Payment)*@Periods;
		END --IF @Rate=0
		ELSE
		BEGIN --IF @Rate <> 0
			SET @term = POWER(1+@rate,@periods);
			
			IF @Type=1
			BEGIN
				SET @Result=@Value*@Term+@Payment*(1+@Rate)*(@Term-1.0)/@Rate
			END
			ELSE
			BEGIN
				SET @Result=@value*@term+@Payment*(@Term-1)/@Rate	
			END
		END --IF @Rate <> 0

        RETURN -@Result  
    END;