Argument 'NPer' must be greater than zero
The NPer function, which returns a Double specifying the number of periods for an annuity based on periodic fixed payments and a fixed interest rate, requires an argument greater than zero.
To correct this error
Check the spelling of arguments in the expression. A misspelled variable name can implicitly create a numeric variable that is initialized to zero.
Check previous operations on variables in the expression, especially those passed into the procedure as arguments from other procedures.