The "spread" of a CDS is the annual amount the protection buyer must pay the protection seller over the length of the contract, expressed as a percentage of the notional amount. For example, if the CDS spread of Risky Corp is 50 basis points, or 0.5% (1 basis point = 0.01%), then an investor buying $10 million worth of protection from AAA-Bank must pay the bank $50,000. Payments are usually made on a quarterly basis, in arrears. These payments continue until either the CDS contract expires or Risky Corp defaults.