These Data Reporting Instructions were developed to assist utility personnel in reporting information to the North American Electric Reliability Corporation’s (NERC) Generating Availability Data System GADS). This reporting system, initiated by the electric utility industry in 1982, expands and extends the data collection procedures begun by the industry in 1963. NERC GADS is recognized today as a valuable source of reliability, availability, and maintainability (RAM) information. This information, collected for both total unit and major equipment groups, is used by analysts industry-wide in numerous applications. GADS maintains operating histories on more than 5,000 generating units. As of January 1, 2013, GADS reporting became mandatory for conventional generating units that are 20 MW and larger. GADS is open to any organization (domestic or international) that operates electric generating facilities and is willing to follow the GADS reporting requirements.