The CODI or Certificate Of Deposits Index is published the first of every month. The CODI is the average of the most recently published monthly yields on 3-month certificates of deposit (secondary market) for the twelve most recent calendar months as published by the Federal Reserve Board ("Index"). 3-month certificates of deposit (secondary market) are an average of dealer offering rates on nationally traded certificates of deposit that are annualized based on a 360-day year or bank interest. The Federal Reserve Board publishes the index in its Federal Reserve statistical release, H-15.

The calculation is averaged by adding the twelve most recently published monthly yields together and dividing the result by twelve (12).  Then this result is rounded to the nearest 1,000th of one (1) percentage.

CODI responds more quickly to the changes in the marketplace than either COFI or COSI.  CODI index is published mid-month. The CODI program works exactly like the COFI and COSI, but the Margins are slightly higher, and the index is slightly more volatile because it has a smaller pool of money deposited as it only includes 3 month C/Ds from Savings & Loans sponsored by the Federal Reserve Board.