From a new RBA FOI release:
How to calibrate the benchmark growth rate? Household debt has been broadly stable as a share of income for about a decade. National aggregate ratios are not robust indicators of a sector’s resilience because the distribution of debt and income can change over time. But as a first pass, it is reasonable to expect that the current level of the indebtedness ratio is sustainable in a range of macroeconomic circumstances. Therefore there does not seem to be a case to set the benchmark growth rate significantly below the rate of growth of household income, in order to achieve a material decline in the indebtedness ratio. With growth in nominal household disposable income running at a little above 3 per cent, this sets a lower bound for possible benchmarks at around 3 per cent. Current growth in investor credit, at nearly 10 per cent, suggests an upper bound around 8 per cent to achieve some comfort about the leverage in this market.
Within this range, there are several options for the preferred benchmark rate for investor housing credit growth (including securitised credit).
a) Around 4½ per cent, based on projected household disposable income growth over calendar 2015. This could be justified as being consistent with stabilising the indebtedness ratio. However, it would be procyclical, in that it would be responding to a period of slow income growth by insisting that credit growth also slow. It would also be materially slower than the current rate of owner-occupier credit growth, which so far has not raised systemic concerns.
b) Around 6 per cent, based on a reasonable expectation of trend growth in disposable income, once the effects of the decline in the terms of trade have washed through. It is also broadly consistent with current growth in owner-occupier housing credit, which as noted above has not been seen as adding materially to systemic risk.
c) 7 per cent, consistent with the system profile for residential mortgage lending already agreed as part of the LCR/CLF process. Unless owner-occupier lending actually picks up from its current rate, however, the growth in investor housing credit implied by the CLF projections would be stronger than this. It is therefore not clear that these projections should be the basis for the preferred benchmark.
Staff projections suggest that only a moderate decline in system investor loan approvals would be required to meet a benchmark growth rate for investor housing credit in the 5–7 per cent range for calendar 2015. The exact size of the decline depends partly on assumptions about repayments through churn, refinancing and amortisation in the investor housing book. For a reasonable range of values for this implied repayment rate, and assuming that investor housing credit growth remains at its current rate for the remainder of 2014, the required decline in investor approvals is of the order of 10–20 per cent. This would take the level of investor housing loan approvals back to that seen a year ago. It is worth noting that investor loan approvals would have to increase noticeably from here to sustain the current growth rate of investor housing credit, even though the implied repayment rate is a little below its historical average.
Since credit is not available at a state level, the benchmark can only be expressed as a national growth rate. The flow of loan approvals at a state level can be used as a cross-check to ensure that the benchmark incentive has had its greatest effects in the markets that have been strongest recently.
Presumably it was APRA that squibbed it out to 10%. Still, with that experience they’ll know better how to tighten if it needed again.
