From the article ... "Statistics Canada reported a significant dip in reported sexual assaults, from the rate of one in 10 to an all-time low of one in 20"
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She then goes on to extrapolate that 1% of all sexual assaults (reported and non-reported) lead to convictions.  Much of the argument for changes is based on these types of extrapolations.  If you are going to compare to other types of crime you need to do so on an even footing.