I wouldn't necessarily confuse application volume to all business schools with application volume to top business schools. For instance, we know MIT had a huge surge in applications this year over last year, and last year over the year before. (Unless they're lying.) Perhaps people are being more wise about how they spend their money in a recession and there is a flight to quality?
That graph is for business schools in general, not for the top business schools.
BTW, I wouldn't cherry pick MIT as one example. Even if overall applications go down, there will be select business schools that see their own applications go up.
I'm more interested in the general case. And after the dot com bust in the early 2000s, the MBA apps went down.