I will quickly clarify something and then ask Mr. Matier to provide a more detailed explanation.
We have our own model. The Department of Finance, for its part, relies on private sector projections. In my remarks, I noted that there was a delay with respect to the 2017 budget because the department once again used the December 2016 projections. That gives you an idea of the distinctions that the Office of the PBO is able to make in its projections. We do regular updates, using our own model.
Christopher, do you want to add to this?