The contract in the case of each kind of these loans provides for a fixed term after which the borrower must repay or renew, and for a fixed rate on the nominal or par value of the loan. Nearly all the securities (bonds, certificates, evidences of indebtedness) are salable at a market rate. It is therefore the income that is fixed, the selling price (or capital value) fluctuating above or below the nominal sum except just at the moment when it is payable. The long-time loan thus is very similar in its economic character to the old-time rent-charge. [Sidenote: The cost of credit to the improvident buyer] 5. _The sale of goods on credit is a mode of lending and involves interest in a disguised form._ In some cases merchants will not sell cheaper for cash than for credit, for fear of offending their main body of credit customers; but this is exceptional, as there are good reasons why such a difference should be made. The credit sale usually involves interest, and often at a very high rate. In many stores there are two appreciably different prices, one for "slow pay," the other for "spot cash." If a bill paid at the end of the month is five per cent. more than the cash price, the difference is equal to sixty per cent. per annum for the privilege of postponing payment. Such a rate of interest is paid only by the improvident, but that is a large class ranging from factory workers to college students. The cash discounts allowed by merchants clearly express the time difference. On fifty to one hundred dollars of outstanding bills, many perfectly honest persons are paying interest at the rate of seventy-five per cent. per annum. The merchant is forced to make this difference because he must seek not only to earn interest on the capital thus invested, but to recover the costs of bookkeeping and collections, and the risk and loss of unpaid bills. The discounts allowed by manufacturers and wholesale houses measure in the same way the difference between cash and credit sales. Not unusual is a discount of "six per cent, in ten days, five per cent, in thirty, or sixty net." The buyer allowing his bills to run for two months (six per cent, for sixty days) pays thirty-six per cent, per annum for the use of that money. The difference is so great that it is impossible to carry on in this way a large business against strong competition. Such purchases on credit frequently are made, however, by dealers in small towns. [Sidenote: Evasion of legal rate of interest]