In 2006 it was about 2.5ยข a litre after-tax profit for the downstream. That's not an absolute calculation; it's an extrapolation using Imperial Oil, Petro-Canada, Shell, and Suncor. They are the only ones that produce that data publicly. They represent about 70% of the refining capacity in Canada, so it's a reasonable proxy for what is represented by the Canadian market.
On June 18th, 2007. See this statement in context.