A huge percentage of all individual tax returns processed by the Internal Revenue Service's modernized account information computer system. Known as the Customer Account Data Engine, or CADE. This system is the centerpiece of modernization efforts at the IRS. CADE is handling significantly more tax returns each year. CADE, which is at the core of the effort to replace many of the agency's aging systems, dramatically speeds up internal IRS processing, permitting taxpayer accounts to update on a daily basis. This helps the IRS better administer the nation's tax system. The IRS is rolling out CADE in a series of "releases," each improving on and adding to the system capabilities. CADE was envisioned to replace the legacy Master File system, parts of which date back to the Kennedy Administration and will eventually house the account information of more than 200 million individual and business taxpayers.