A renewed surge in Melbourne property prices is driving continued double-digit home price growth across the combined capital cities.

While Sydney retains the highest year-on-year property price increase at 16.7 per cent, CoreLogic RP Data's figures show that it is slowing and Melbourne is rapidly catching up.

The CoreLogic figures from September show Sydney prices rose a mere 0.1 per cent last month and 4.6 per cent in the September quarter.

In contrast, Melbourne property prices jumped 2.4 per cent last month and 7.4 per cent over the September quarter, for a 14.2 per cent rise over the past year.

CoreLogic RP Data's head of research Tim Lawless said the convergence of the two major markets is also evidenced by auction results.

"We're seeing Sydney and Melbourne recording virtually identical clearance rates in the low 70 per cent mark," he told ABC News Online.

"Sydney peaked out at about 91 per cent for clearance rates earlier this year, whereas Melbourne only got as high as the low-mid 80s."

Mr Lawless said Melbourne is currently experiencing "an unsustainable rate of growth" with rental yields for houses falling below 3 per cent for the first time on records going back to 1996.

"We wouldn't expect values to be rising that fast for extended periods at a time when rents are hardly moving - Melbourne rents are only up by less than 1 per cent the past 12 months - and, of course, household incomes are hardly moving as well," he added.

But while Australia's two biggest cities remain in boom times and the third biggest, Brisbane, records solid 4.6 per cent annual growth, the rest of the country is flat or going backwards.

Darwin's 3.9 per cent fall over the past year was the steepest, but Perth, Adelaide and Hobart were also in the red.

The nation's capital managed only a 0.6 per cent gain.

Mr Lawless said the mining slowdown was seeing fewer people move to mining regions, and many move away to the south-eastern cities.

"We've seen a real slowdown in the rate of overseas migration into markets like Western Australia and Queensland and the Northern Territory, whereas in Victoria and New South Wales we're seeing population growth that's hardly been affected at all by a slowdown in migration," he observed.

That trend was highlighted in recent ABS data that showed more people leaving Western Australian for other states than coming to it and the slowest Northern Territory population growth in more than a decade.

However, with the biggest cities growing fastest, CoreLogic's national combined capitals index showed growth of 0.9 per cent last month and 11 per cent over the past year.