Melbourne’s robust auction market looks set to end the year on a downward slide, with the city’s clearance rate tracking below 70 per cent for the past two months.

The results are in stark contrast to this time last year when results were more bullish, holding above 70 per cent from July through to the end of 2016.

More than 40,000 houses and units across Melbourne have gone under the hammer in 2017, according to the Domain Group, and a further 1400 are listed to go to auction on Saturday.

But while the city’s property market continues to outperform Sydney, where clearance rates have fizzled out to 50 per cent, economists have warned Melbourne is showing early signs of following the harbour city.

“If you look at auction clearance rates, Sydney is leading Melbourne down,” said AMP chief economist Shane Oliver.

Domain Group chief data scientist Nicola Powell said 60 per cent was considered a benchmark for house price inflation, whereby clearance rates above that level indicated a high level of demand and price growth.

“What we’ve seen in the Sydney and Melbourne markets is a bit of a changing of the tide,” Dr Powell said.

Monthly clearance rates over winter and spring in Melbourne were lower than previous years, she said, but added that the results were still “more robust” than Sydney.

Mr Oliver said Melbourne auctions were holding up better than Sydney partly because the gains in Victorian property prices had been more moderate.

“It has still been strong but the boom in Sydney was a lot bigger, so affordability is a lot poorer than in Melbourne.”

“The Sydney market has become more speculative and, on the way up, it’s become a lot more bubbly,” he said.

Despite strong population growth, Mr Oliver predicts clearance rates and property prices will slow in Melbourne. “There is some chance that Melbourne might not see as deep a price fall as Sydney because Melbourne never went up as much,” he said.

Real Estate Institute of Victoria president Richard Simpson said it had been a seller’s market for most of 2017, but the tables had begun to turn.

“Consistently high auction volumes throughout spring and the start of summer saw supply start to meet buyer demand…”

Mr Simpson said lower clearance rates may mean some sellers would delay listing their property until later in 2018.

“While we expect price growth to moderate in 2018, high interstate and overseas migration will continue to drive demand for housing in the city’s inner and middle rings.”

Mr Simpson said the city’s outer suburbs were standout performers, with Hoppers Crossing, Sunbury and Mill Park recording overall clearance rates at or above 85 per cent.

“Increased demand for affordable housing will see strong price growth in established outer suburbs in 2018, with auction volumes expected to rise in these areas.”

In the inner east, home to some of Melbourne’s wealthiest postcodes, clearance rates have been steadily falling since autumn, hitting 55 per cent earlier this month.

Auctioneer Justin Long from Marshall White said auction clearance rates were not always a good indicator of the strength of the local market.

“I’ve long held this feeling that when clearance rates drop, the vendors have started creeping ahead of the market, which can be very tempting,” he said.

He said vendors with unrealistic expectations were behind many family homes that pass in.

“We’ve had a lot of vendors that have hiked up their reserves at the last minute.”

Among the 1410 properties scheduled to go under the hammer on Saturday is the family home of Kate and David Stephenson.

Mr Long will be auctioning 29 Gordon Grove in Malvern, where the Stephensons have lived and raised their two children over the past 23 years. Mrs Stephenson has recently taken to spending her Saturdays at other auctions in the area, “just to get used to them”.

“There was one the other day that was quite exciting,” she said. “But two others passed in.”

The couple said they took their real estate agent’s advice to go to auction. “We’re feeling pretty positive. If it does get passed in, it’s not the end of the world.”