Well, I wouldn't say that (but I'm not a criminal law professor). I would say that about half are for violent crime, about 20% each for property crimes and drugs crimes ... the proportion for violent crime has been going up while the proportion for drugs has been going down
Table 12 is interesting (page 9 for people with no time to browse).
http://www.ojp.usdoj.gov/bjs/pub/pdf/p04.pdf