Institutions Matter: The Cross-country Dimension

On the first, we can summarise by saying that institutions matter. Country-specific features are very important to housing outcomes, including the outcomes most relevant to monetary and financial stability policymakers.

A range of institutions determine the idiosyncratic risk that households face, and thus the credit risk they pose to lenders. These include labour market institutions, the funding of health care, and the structure and generosity of the social safety net.

Geographic and other factors determine the urban structure, which in turn affects the relative price of housing. We know from economic geography that as city populations rise - and the amenities that go together with that - housing prices rise even relative to the higher incomes that often go along with big-city living. So urban concentration affects macro-level variables, like the ratio of housing prices to household incomes, as well as individual-level outcomes, such as people's lifetime housing experiences.

The structure of the mortgage market matters, for example whether fixed or variable-rate mortgages predominate. These features are in turn affected by a range of tax and other institutional factors. An example of a feature quite specific to Australia is the popularity of linked offset accounts. These change the interpretation of debt data that do not adjust for balances in these accounts. They also change assessments of the resilience of the household sector to various kinds of shocks.
Taken together, these factors suggest that we can't assume a single value of any particular macro-level ratio exists that is 'right' for all countries or for all time. It depends. We can't assume that a particular level of debt is always and everywhere sustainable. It depends on who has the debt and what kind of credit risk they pose. We can't assume that a particular level of prices is 'correct' or 'sustainable' in all circumstances.

What we can do is get some sense of the relativities between countries that you might expect, given those institutional and other differences. For example, we can reasonably expect that countries where much of the population lives in smaller, cheaper cities will have lower national aggregate ratios of housing prices to incomes than other countries. That might partly explain why the price-to-income ratio for the United States is relatively low (Graph 1). By contrast, Australia is somewhere around the middle of the pack of mid-sized countries on this metric.