The fact that significant numbers of households have had their potential borrowing power crimped by lending standards belatedly being tightened, and are therefore mortgage prisoners, is significant. As we reported recently, up to 40% of those seeking to refinance are now having difficulty. This is strongly aligned to those who are registering as stressed. These are households urgently trying to reduce their monthly outgoings.
Continued rises in living costs – notably child care, school fees and fuel – whilst real incomes continue to fall and underemployment is causing significant pain. Many are dipping into savings to support their finances. The June 2018 household savings ratio, just reported, shows a further fall, at 1%. The ABS says  "moderate growth in household disposable income coupled with strength in household consumption resulted in a decline in the household saving ratio to 1.0 per cent, recording its lowest rate since December 2007".
Our analysis uses the DFA core market model which combines information from our 52,000 household surveys, public data from the RBA, ABS and APRA; and private data from lenders and aggregators. The data is current to end August 2018. We analyse household cash flow based on real incomes, outgoings and mortgage repayments, rather than using an arbitrary 30% of income.
Households are defined as "stressed" when net income (or cash flow) does not cover ongoing costs. They may or may not have access to other available assets, and some have paid ahead, but households in mild stress have little leeway in their cash flows, whereas those in severe stress are unable to meet repayments from current income. In both cases, households manage this deficit by cutting back on spending, putting more on credit cards and seeking to refinance, restructure or sell their home. Those in severe stress are more likely to be seeking hardship assistance and are often forced to sell.