Best Interest Report:

A 2.5-year jumbo CD (certificate of deposit) is a time deposit, FDIC-insured to $100,000 per person ($250,000 on retirement accounts), with a fixed maturity date of 2.5 years. It usually pays higher interest than a savings account and a penalty is charged for withdrawing funds before the maturity date. Jumbo CDs have a very high minimum -- $100,000 is common -- and they pay higher rates than smaller-denomination CDs.

The highest rate on a 2.5-year CD nationally is 2.80 percent, with an annual percentage yield of 2.84 percent. Six months ago, the average yield was 1.84 percent.

The yield on a CD is higher than the rate because the yield takes compounding into account. Of the 5,558 institutions that Bankrate surveys nationally that sell 2.5-year CDs, 4,242 institutions offer daily compounding, 483 institutions offer monthly compounding and 717 institutions offer quarterly compounding. For consumers, more-frequent compounding produces a higher total yield.

Institutions also have different minimum deposit requirements. Bankrate's survey found the minimum for a 2.5-year CD ranged from $1.00 to $10,000.00.

Some institutions sell their CDs only in their local market; others sell CDs nationwide. Click here to see the 100 highest yields on a variety of CDs available nationally.

To see all of the results of Bankrate.com's surveys, go to www.bankrate.com.

The Your Best Interest report is a daily service of Bankrate.com, a financial news and information service based in North Palm Beach, Fla. Bankrate surveys more than 300 financial products from more than 4,800 institutions in all 50 states.