(1)Every tenant shall pay rent within the time fixed by contract or in the absence of such contract, by the fifteenth day of the month next following the month for which it is payable [and where any default occurs in the payment of rent, the tenant shall be liable to pay simple interest at the rate of fifteen per cent. per annum from the date on which such payment of rent is due to the date on which it is paid] [Added by Act 57 of 1988, section 14 (w.e.f. 1-12-1988).].