You're raising an interesting point. We have to remember that interest payments, on public debt in this case, are a form of transfer. They're a transfer from the government budget—but of course that's really the taxpayers' budget—to bondholders.
Of course, the taxpayers tend to be in the upper-income groups, at least when it comes to public debt, and the interest paid on it of course goes to bondholders, many of whom are outside the country. As I mentioned, about a quarter of them are, so it's actually a drain on resources for the country when taxpayers are covering these interest expenses. As far as inequality impacts go, I think that's where the household debt becomes particularly relevant. Of course many middle-income groups have taken on significant household debt. In fact the numbers that you gave—400% of GDP for household, non-financial corporate and public debt—are based on IMF data. That doesn't even include all of the financial obligations that the governments have in Canada, which I've emphasized in the past.
In terms of that household debt and its impact on inequality, I have to admit that I haven't really looked at that very carefully, but certainly when you get borrowers who are getting low interest rates right now, maybe that's not as much of a problem for those individuals. The big problem, of course, comes down the road when they renew their obligations and they are facing higher interests rates. That is bound to happen as we get past this and into the recovery.