NPER function


Returns the number of periods for an investment based on periodic, constant payments and constant interest rate.



=NPER( ratepmtpv[fv][type] )


required arguments:

rate The interest rate per period.
pmt The payment made each period.
pv The present value, or a total value of all payments.


optional arguments:

[fv] The future value.
[type] 0 = end of period. 1 = beginning of period. Default is 0.