Return the number of regular payments of p necessary to amortize a loan of amount a and interest r.
The optional argument l may be used to specify an additional lump-sum payment of l made at the end of the amortization time.
The optional argument method may be used to specify whether payments are made at the end ("e", default) or at the beginning ("b") of each period.
Note that the rate r is specified as a fraction (i.e., 0.05, not 5 percent).
See also: pv, pmt, rate, npv.
Package: financial