A critical variable in the money market is the interest rate. Although we sometimes talk as if there is only one interest rate, there is never just one interest rate at any time. Instead, the interest rate on a given loan reflects the length of the loan and the perceived risk to the lender. A business that is just getting started must pay a higher rate than General Motors pays. A 30-year mortgage has a different interest rate than a 90-day loan. Nevertheless, interest rates tend to move up and down together, and their movement reflects general conditions in the financial market.