You're right. The data that we present—which I think you have available to you but I can share as well—shows that McKinsey has the highest rate of growth by far between 2017 and 2021. The overall total amount spent on McKinsey is much smaller than a number of other firms.
Why has it grown so much? I can't speculate. I really don't know.
It's possible that the data is not actually that strong from the baseline point that we have. Something we've mused about is why it was such a small amount in 2017. There may be data entry errors or it could just be that year they didn't happen to get a lot of contracts, so it looks like a lot but it's actually not a huge change.
It's interesting that, when I speak to public servants about the firms they are worried about, they very rarely say McKinsey. More often—it depends on the case—it's Deloitte. PricewaterhouseCoopers comes up a lot, as does Accenture. Some of the big IT firms basically act like management consultant firms now, like IBM, which is another one that comes up a lot.
As for the growth for McKinsey, I haven't seen any reliable evidence to suggest why that's the case.