Thanks, Mr. Chair. That is a great question.
In our opinion, based on the analysis we've done, a lot of it has to do with the fact that supply has not kept up with demand for housing in recent years. We estimate that back in 2004.... That's the baseline for a lot of our study on supply gaps. That was a time when affordability was relatively good across Canada, at least from a historical perspective. Since that period of time, a supply gap has grown to reach about two million units as of right now, and we project that's going to grow in the years ahead to about three and a half million units by 2030.
That supply gap is one of the key reasons that we're seeing a deterioration of affordability. If something isn't done about it, I suspect you're going to continue to answer questions from your constituents in the years to come. As that supply gap gets larger, we're going to see more affordability pressures in terms of ownership of housing, but also within the rental market. We can't forget about that.
We're now collecting new data on rents, and not just on average rents. We look at rents for folks who stay in the same unit versus rents in apartments that turn over. In Toronto last year, the rent increase for people who stayed in place was about 2.3%. When a unit changed hands, the rent increase was a little above 29%. That gives you an idea of what happens when you have a supply-constrained market. People change units for whatever reason, or new people come to live in that market, and they're facing a market that's very supply-constrained, and that drives costs higher.
It is a big problem, but one that needs supply in order to fix.