Very briefly, the adjustment for the Canadian core and total CPI is that what is removed from total CPI are the most volatile items in that basket. But what is important here is that while there's less variation in core CPI—and core CPI is the best predictor of future CPI levels, so you see much bigger swings in total CPI—if you look over a longer period, the level of those prices as they move over time is consistent. So for core CPI in Canada--not uniquely, but it's relatively unusual--it is much more the case here that core is a good predictor of total CPI. You have higher variance; both move in tandem.
On April 27th, 2010. See this statement in context.