This is an important reason why I look forward to any progress in this field, whether we can ever fine-tune macroprudential policy or not. My third and final point on conceptual issues is that, ideally, the prudential stance should also account for the interaction of macroprudential policies across countries. Euro-area countries are deeply integrated.
During stress periods, this may lead financial instability in one country to propagate to other countries, if an inaction bias prevails; the same holds, again symmetrically, for the effect of contractionary measures. How, and to what extent, this can be done is, I think, a matter for further potentially valuable reflection.