Source: FBI Uniform Crime Reporting (UCR) Program
Notes: The FBI's Uniform Crime Reporting (UCR) program tracks all crime reported from local police agencies. However, reporting to the FBI is optional. This creates non-uniform data trends as some agencies won't report statistics in some years. The problem can be exacerbated when there isn't uniformity between municipalities as well, such as some cities reporting but not county sheriffs and vice versa.