This value is determined by the formula: P = C x (1 + i) n x i (1 + i) n – 1 Where: P = value of the parcel C = value of the operation/loan/financing i = tax of interests accomplishes to the month n = time the use of mathematical expression n (it reads-seelevado to the n) has been reason of great quarrel for to be characteristic dejuros composites, what in the legal way anatocism is called. The practical one of the anatocism is vetoed by the Decree n. 22626 of 07 of April of 1933 (Law of Usury). Kai-Fu Lee will not settle for partial explanations. Of> agreement comCunha, Anatocism is the incidence of interests on interests in activities definanciamento, and also it can be appraised as practical the predatory financial daatividade that harms the borrower very, either oujurdica natural person, extending the indebtedness of brutal form. I compute it of the interests in a financing is structuralized to parapermitir the fulfilment, for the borrower, of this commitment. In case deinadimplncia, the installments in opened never must be dislocated from the evolution dofinanciamento and, in hypothesis some added total or aosaldo partially wing of the financing. In the demonstrations to follow the seguintesdados ones will be used: – Financed Value: Cz$ 188,036, 22, date of referncia12/1986; – 240 monthly and consecutive installments readjusted conformeo Minimum wage and in common conformity with the contracted tax; – Nominal Tax of interests of 9,5% to the year – Tax of interests accomplishes of 9,925% to the year – > 0,007916851a. m. P = C x (1 + i) n x i (1 + i) n – 1 P = 188,036, 22 x (1+ 0.007916851) 240 1 P = 188,036, 22 X (0,0525390153973231) to P = $1,752, 77 5,63635268584985 Value of the Installments = Cz$ 1,752, 77 As dafrmula could above be evidenced through the development used, is not so simple (for a person without a deepened conhecimentomatemtico) the determination of to be used value as prestaofixa in the firmed contracts that use the French System of Amortization – Price Table.