Report author professor Paul Gallimore from Massey's School of Economics and Finance said the situation tends to bite harder at first homebuyers, especially in Auckland.
"If you look only at the last quarter, hikes in prices have really dominated, with around 85 percent of the change in the national index over that period due to this factor," he said.
All other regions are more affordable than the national average with Canterbury 5 percent below, Nelson/Marlborough and Waikato both 13 percent below and Manawatu/Whanganui 42 percent below. Southland remains the most affordable place to buy a house in the country at 54 per cent below the national median.
Gallimore expects housing affordability to continue to deteriorate this year and, in Auckland, to potentially reach levels not seen since the global financial crisis.
"While Auckland's affordability score still remains below the peaks seen in 2007/2008, its current trajectory suggests it may soon return to or exceed those levels," he says.
"Even without further price rises - which not one is predicting, a one percentage point rise in interest rates, without substantial wage increases, would put it on par with 2007/2008 levels,".
The Reserve Bank this morning left the official cash rate unchanged at 3.5 per cent and abandoned its tightening bias for interest rates.