Annual Percentage Yield Calculation Program for Windows (APYWIN)

The APYWIN program has been discontinued. Refer to OCC Bulletin 2020-40 or visit the FFIEC Federal Disclosure Computational Tools at

The Windows-based version of the Annual Percentage Yield program (APYWIN v2.1 - Release May 2009) is an efficient tool for verifying annual percentage yields pursuant to the Truth in Savings Act (12 U.S.C. 4301 et seq.) and its implementing regulation (Regulation DD, 12 CFR 230).

The APYWIN 2.1 program is only available for download (ZIP).

You can also provide comments and feedback to the address below:

Office of the Comptroller of the Currency
Compliance Policy
Mail Stop 6-6
Washington, D.C. 20219

Although great care has been taken in the preparation of this APY program, the OCC makes no warranty of complete accuracy. Further, the OCC does not recommend this program over other methods to calculate annual percentage yields.

The APYWIN 2.1 installation will automatically uninstall any earlier version of the APY program from your computer. If you have APY v1.0 (DOS) and would like to keep this version, please follow the steps below before installing the new version.

  1. In Windows Explorer, go to the folder where you placed APY v 1.0, the default location is C:\APY.
  2. Copy the entire APY folder and paste it into another directory of your C: drive.
  3. Run the 1.0 version from the new directory location.

Download the Program

To download APYWIN 2.1 to your machine, follow the instructions below. (Note: The file size is approximately 3MB.)

  1. Download one compressed file ( to a temporary folder on your hard drive.
  2. Execute apywin-software-exe.exe to begin the installation program.
  3. Follow the prompts.

Please note that the APYWIN 2.1 application is not currently supported on Windows Vista.