Installed in 1996, the Airport Noise Management System (ANMS) enables the City of Chicago to monitor the amount of noise being generated over the communities surrounding O'Hare by the aircraft operating at the Airport. The ANMS collects, analyzes and processes data from a number of sources of information including a network of 36 noise monitors around O'Hare, FAA radar data, weather data and noise complaints. Over 150,000 flights and 400,000 noise events are recorded by the ANMS each month for the Chicago Department of Aviation. The City of Chicago and the O'Hare Noise Compatibility Commission utilize data from the ANMS to facilitate the development and management of noise abatement programs at the Airport. The following reports summarize pertinent monthly information from that data concerning the noise levels and operations at the Airport.