UCR definitions are here:
http://www2.fbi.gov/ucr/handbook/ucrhandbook04.pdf
You can get crime data submitted to the FBI at city-data. Just type the city name and add “city data” to your google search. The nice thing about city-data is you get 10 years’ worth. San Diego PD has data going back to the 50’s. Per capita violent crime tripled in the 60’s and went far higher in the 70’s and 80’s, but have now settled back to the high 60’s rate. This is why news bureaus always talk about crime rates having gone back to 60’s rates, as if the nation has become a land of Mayberry’s. In reality, crime rates are historically high relative to the 50’s and before, and obviously much higher than in Western Europe.
San Diego stats:
http://www.sandiego.gov/police/pdf/2013/UCRRates1950to2012.pdf