From the developer: "This software calculates the return on investment (ROI) for any scenario. The user inputs cash flows (money in or money out) and the corresponding dates. Individual and/or periodic transactions are accepted. Sophisticated mathematics give the ROI. Great for playing 'what if' by investors and business decision makers. The 3 page instructions assume the user has NO EXPERIENCE and starts with the definition of ROI. This software expires 30 days after installation, or after ten user sessions, unless registered for $29 (US)."