What the CGPI measures, and what it does not

The Canadian Grocery Price Index (CGPI) is a weekly measure of what a fixed basket of 50 everyday grocery items costs across major Canadian retailers. It is a chained, matched-model weighted Jevons index: each week is compared with the week before over the items priced in both weeks, and those weekly links accumulate into the published level. That construction is what lets us say a move is a real price change rather than a change in which products happened to be on the shelf.

As of the latest release the national index stands at 101.5, down 0.2% on the week and down 1.8% since the series began in June 2026.

What it can support

Week-over-week direction and magnitude for the national index, for each of the nine basket categories, and for individual cities and banners that clear the publication threshold. Because collection runs weekly, the series moves well ahead of the monthly Statistics Canada CPI print — that lead is the point of it.

What it does not support

Year-over-year comparisons: the published series begins in June 2026, so there is no prior-year base to compare against, and we do not publish a YoY figure rather than imply one. Cross-city comparisons of the index level: each series is rebased to 100 in its own entry week, so levels are not comparable between series — compare absolute basket cost in dollars instead, which is what our comparison tool does by default. And it is not a total-food-inflation measure: Walmart and Costco are not in the panel, and a cell only publishes once at least 60% of its basket slice is priced in both linked weeks.

Every published figure carries its coverage and its methodology version, and the coverage page states the gaps in plain language. The point is not that the measure is perfect; it is that a reader can see exactly where it is strong and where it is thin.