ALTER FUNCTION [dbo].[eConvertToBLR] (@Calculation bigint, @Currency nvarchar(3), @Amount money )
RETURNS money
AS
BEGIN

RETURN( select  round(@Amount * case @Currency
                                    WHEN 'RUR' THEN RateRUR 
                                    WHEN 'LTL' THEN RateLTL 
                                    WHEN 'USD' THEN RateUSD 
                                    WHEN 'EUR' THEN RateEUR 
                                    WHEN 'UAH' THEN RateUAH  
                                    ELSE 1
                                end
                     , 2
                     )
          from tblMonthlyVariables WHERE ID=@Calculation
      );
END;