As Kady suggests, Stock must have been referencing the 2004 National Victimization Survey, part of the General Social Survey, which is conducted every five years, when he argued this morning that Canada had seen an "alarming" increase in "unreported crime". Forget that the latest report dates from 2004 and tells you nothing about what's happened since. Here's what it says in one of the fact sheets for the General Social Survey. They're referring to "violent crimes":
Police reporting rates remain stable
Rates of reporting violent incidents to the police remained stable between 1999 and 2004. In 1999, 31% of violent incidents were reported to the police, compared with 33% of incidents in 2004. This difference was not statistically significant.
Mind you, when it comes to overall reporting, Stock isn't entirely off his nut:
The GSS reveals that a large proportion of Canadians never reported criminal incidents to police. In all, only about 34% of criminal incidents came to the attention of police in 2004, down from 37% in 1999. Household victimization incidents were most likely to be reported (37%), while thefts of personal property were the least likely (31%).
I'll leave it to the reader to decide whether or not a three per cent drop in reported criminal incidents is "alarming".