Fuel consumption US Yaris vs. Canadian Yaris

[Driver]

While waiting for my Yaris to arrive from wherever it's being made, I've been looking at The Toyota sites in other countries. I notice that in the US the ads say the Yaris gets 34 Mpg city and 40 Mpg highway, and in Canada it's 41 Mpg city and 51 Mpg highway. Many folks say that they mean KMPG. I don't think so because I'm sure a Canadian site would know better. I also know there's a big difference in the pollution controls required between the countries ours being much more stringent. So What kind of mileage are the folks in Canada getting in Mpg's?