A measure of the real cost of housing is the mortgage repayment percentage when compared to income.
Figures produced by the Reserve Bank of Australia show the figure of “Interest payments to disposable income” from 1977.
This table shows how the percentage has been increasing over the years.
| Year | Rate |
| Jun-1977 | 3.75% |
| Jun-1978 | 3.61% |
| Jun-1979 | 3.72% |
| Jun-1980 | 3.85% |
| Jun-1981 | 4.05% |
| Jun-1982 | 4.34% |
| Jun-1983 | 4.24% |
| Jun-1984 | 3.91% |
| Jun-1985 | 4.01% |
| Jun-1986 | 4.69% |
| Jun-1987 | 5.22% |
| Jun-1988 | 4.73% |
| Jun-1989 | 5.67% |
| Jun-1990 | 5.61% |
| Jun-1991 | 5.02% |
| Jun-1992 | 4.01% |
| Jun-1993 | 4.21% |
| Jun-1994 | 4.33% |
| Jun-1995 | 5.44% |
| Jun-1996 | 5.51% |
| Jun-1997 | 4.51% |
| Jun-1998 | 4.57% |
| Jun-1999 | 4.54% |
| Jun-2000 | 5.77% |
| Jun-2001 | 5.25% |
| Jun-2002 | 5.81% |
| Jun-2003 | 6.32% |
| Jun-2004 | 7.46% |
| Jun-2005 | 8.38% |
| Jun-2006 | 8.91% |
| Jun-2007 | 9.49% |
| Jun-2008 | 11.12% |
| Jun-2009 | 7.63% |
| Jun-2010 | 9.70% |
The peak was in 2008, with 11.12% of disposable income being used for Interest payments on Household Mortgages, although after a drop in 2009, to near 2004 levels, the rate again increased back up to the 2007 level, showing 9.7%.
The source for the above is the RBA B21 Household Finances spreadsheet.
This chart shows the rate of Housing Loan Interest payments to disposable income, and Housing Assets to disposable income for each year.
| Year | Interest payments | Housing Assets |
| Jun-1977 | 3.75% | 387.0 |
| Jun-1978 | 3.61% | 382.4 |
| Jun-1979 | 3.72% | 374.9 |
| Jun-1980 | 3.85% | 392.2 |
| Jun-1981 | 4.05% | 400.8 |
| Jun-1982 | 4.34% | 381.1 |
| Jun-1983 | 4.24% | 385.9 |
| Jun-1984 | 3.91% | 392.0 |
| Jun-1985 | 4.01% | 409.4 |
| Jun-1986 | 4.69% | 408.5 |
| Jun-1987 | 5.22% | 423.0 |
| Jun-1988 | 4.73% | 466.5 |
| Jun-1989 | 5.67% | 482.9 |
| Jun-1990 | 5.61% | 457.8 |
| Jun-1991 | 5.02% | 464.1 |
| Jun-1992 | 4.01% | 486.0 |
| Jun-1993 | 4.21% | 496.4 |
| Jun-1994 | 4.33% | 515.2 |
| Jun-1995 | 5.44% | 518.8 |
| Jun-1996 | 5.51% | 505.2 |
| Jun-1997 | 4.51% | 534.6 |
| Jun-1998 | 4.57% | 558.8 |
| Jun-1999 | 4.54% | 592.1 |
| Jun-2000 | 5.77% | 616.2 |
| Jun-2001 | 5.25% | 625.7 |
| Jun-2002 | 5.81% | 656.3 |
| Jun-2003 | 6.32% | 684.0 |
| Jun-2004 | 7.46% | 729.8 |
| Jun-2005 | 8.38% | 740.6 |
| Jun-2006 | 8.91% | 769.2 |
| Jun-2007 | 9.49% | 782.2 |
| Jun-2008 | 11.12% | 737.3 |
| Jun-2009 | 7.63% | 670.1 |
| Jun-2010 | 9.70% | 750.0 |
From June 1977 to June 2010, the rate of Interest payments to disposable income rose by 258%.
However, during the same period, the rate of Assets to disposable income only rose by 194%.