We did attempt to cost the impacts of climate change on the Canadian economy between now and 2100. We have estimated, in our best attempt at estimating, the most likely impacts of climate change on the Canadian economy. What we have not done is compare a world where nobody acts on climate change with the so-called “benefit” of acting on climate change, because this is a very difficult counterfactual to find.
We have estimated the cost of the carbon tax, how much households will receive, how much it will cost, the cost of climate change and so on, but we have not found a credible, reliable model that would allow us to tangibly cost the benefits of acting on climate change. And even if we did, we'd have to assume that in that counterfactual nobody does anything on climate change, which is not very credible. That's the difficulty of trying to estimate the benefit of implementing a carbon levy or a carbon tax and other actions to fight climate change.