Item 7A. MARKET RISK

We had $497.3 million of cash and investments on December 31, 2008, consisting of $494.7 million of cash and cash equivalents and $2.6 million of available-for-sale securities. Although these investments are subject to the credit risk of the issuer, we manage our investment portfolio to limit our exposure to any one issuer. Substantially all of the cash equivalents are money market securities from treasury and tax exempt money issuers. All of our available-for-sale securities are high-quality bonds that are exempt from U.S. federal income taxes. Because of the credit risk criteria of our investment policies and practices, the primary market risks associated with these investments are interest rate and liquidity risks. We do not use derivative financial instruments to manage interest rate risk or to speculate on future changes in interest rates. A rise in interest rates could negatively affect the fair value of our investments.