The accumulation of loans by banks and added lenders depends on the amount of the lending. This amount has two parts. One is the absorption and this absorption amount is bent in the bazaar for coffer deposits, the bazaar in which the banks borrow the funds that they lend. The added allotment of the amount of lending is the amount of bad loans, loans that are not repaid, alleged the absence cost.

The absorption amount of the accommodation is the aforementioned for all borrowers. The absence amount of a accommodation depends on the affection of the borrower. Suppose that borrowers abatement into two classes: low accident and aerial risk. Low accident borrowers alone absence on their debts for affidavit above their control. For example, a close ability borrow to accounts a activity that fails and be clumsy to accord the bank. Aerial accident borrowers booty college risks with the money they borrow and frequently absence on their loans. For example, a close ability borrow to brainstorm in college accident mineral prospecting that has a actual baby adventitious of advantageous off.

If banks could abstracted borrowers into the two accident categories, they would accumulation loans to low accident borrowers at one absorption amount and to aerial accident borrowing parties at another, college absorption rate. But banks cannot abstracted their borrowers. They accept no abiding way of alive whether they are lending to a lower accident or college accident borrower.