(RATE3(pv,pmt,per))
Returns the periodic interest rate required for an annuity of value pv, to return a series of equal payments, pmt, over a number of compounding periods, per.
In the following example, RATE3 returns the interest rate of an annuity, purchased at $50,000, which will pay $570 monthly for 10 years. The value of vrate3 is .0055, a monthly rate of .55 percent, or 6.6% annually.
SET VAR vrate3 = (RATE3(50000,570,120))
