numpy.pv

numpy.pv(rate, nper, pmt, fv=0.0, when='end')

Compute the present value.

Parameters:

rate : array_like

Rate of interest (per period)

nper : array_like

Number of compounding periods

pmt : array_like

Payment

fv : array_like, optional

Future value

when : {{‘begin’, 1}, {‘end’, 0}}, {string, int}, optional

When payments are due (‘begin’ (1) or ‘end’ (0))

Returns:

out : ndarray, float

Present value of a series of payments or investments.

Notes

The present value pv is computed by solving the equation:

fv +
pv*(1 + rate)**nper +
pmt*(1 + rate*when)/rate*((1 + rate)**nper - 1) = 0

or, when rate = 0:

fv + pv + pmt * nper = 0