The present value coefficient of compound interest, that is, if you invest a sum of money P now, the sum of principal and interest at the end of each period will be used as the principal of the next period, and the interest will continue to be calculated according to compound interest, and so on. By the end of a period, the sum of principal and interest multiplied by the coefficient (P/F, I, N) should be equal to the amount of money invested now.
Expressed by the formula, p = (p/f, I, n) * f.