It's at least 80%, so this is not a distinctive finding. The base rate of the use of Internet pornography is very, very high among non-rapists, as well as sexual criminals.
The second question has to be whether it is the fact that sexual criminals who possess a variety of anti-social personality traits, etc., are attracted to pornography and sexual criminality, or whether this is a spurious relationship. It's there, but it's not there in a causal role.
The best evidence I can give you, again trying to look at the systematic science, is that multiple studies of convicted sexual offenders, in contrast to the FBI, show less use of pornography by sex offenders than by other people—by comparator groups. Whether this is a causal factor or not, I can't tell you; I don't know in those particular situations. I can tell you that the baseline rate of use of pornography among young males, for example, who represent sexual criminals, at least age-wise, is very high, and that the systematic studies generally suggest that sex criminals are not distinctive in their use of pornography.
I would also look at the general rates of sexual assault, which, in the context of unlimited access to pornography, have not increased.