The Uniform Crime Reporting (UCR) program compiles official data on crime in the United States, published by the Federal Bureau of Investigation (FBI). UCR is "a nationwide, cooperative statistical effort of nearly 18,000 city, university and college, county, state, tribal, and federal law enforcement agencies voluntarily reporting data on crimes brought to their attention". The Uniform Crime Reporting program began in 1929, and since then has become an important source of crime information for law enforcement, policymakers, scholars, and the media.