I've recently updated that study to 2011-21. There were 550,000 in the 2011-21 period. Of course, the number is going down because there aren't enough units left under $750 to disappear in the first place, and we see a movement up to the next rent band of $750 to $1,000 where we're seeing that erosion as well.
What we're seeing there are a number of things. There's the absolute loss. In some cases some of those units are lost as a result of intensification pressures. Many cities are building in our inner city areas, which is where we happen to have built the old rental housing in the 1960s and 1970s, so they're being knocked down and replaced. It's one area of loss, although that's quite small.
Second, some is potentially lost—as in the discussion we previously had—to the short-term rental market.
The vast majority are not lost in absolute terms, as they still exist, but the rents have significantly moved upmarket. When we see rents going up by 18%, 19% or 20%, those units move very quickly.
We have seen some predatory behaviour with investors and various asset management firms trying to purchase low-rent properties specifically for the purpose of trying to increase yield by repositioning those assets in the market and raising the rents. It's a function of that kind of behaviour, and as I mentioned in my presentation, it's enabled by rent regulation that makes that perfectly legitimate and legal to happen through vacancy decontrol and turnover.