The interest rate that the Federal Reserve charges a bank to borrow funds when a bank is temporarily short of funds. Collateral is necessary to borrow, and such borrowing is quite limited because the Fed views it as a privilege to be used to meet short-term liquidity needs, and not a device to increase earnings. In context of NPV or PV calculations, the discount rate is the annual percentage applied. In the context of project financing, the discount rate is often the all-in interest rate or the interest rate plus margin.
Copyright © 2011 Campbell R. Harvey, Professor of Finance, Fuqua School of Business at Duke University