I can't give you an order of magnitude in terms of a figure. What I can say is that in the particular case of urban transit, exactly because of the scenario you're painting, dedicated transit funding is essential. Municipalities simply can't live on the gas tax and the property tax.
Part of your question was on what other avenues there are to span that gap between the gas tax and the needs, and the property tax is the most significant one.
In comparison globally, Canadian municipalities rely on the property tax for significantly more than other OECD countries. In Canada the property tax makes up roughly 60% of municipal revenues. In the United States, for example, it's about 20% to 25%, and in OECD countries the standard is closer to 30%. We rely heavily on the property tax; it is the other major source of revenue. So the only option is to increase the property tax, which increases the tax burden on Canadians on where they live.
We think that if there's dedicated transit funding in the context of a longer-term infrastructure plan, you're going to complement the gas tax with the kinds of resources over the long term that will be needed for these kinds of challenges.