The property listings site said it was a substantial drop compared to the average fall of -1.1% measured in August over the past 10 years.
The Olympics distraction did not deter new sellers from coming to market during August, with numbers marginally up on the same period a year ago with 127,992 properties coming to market this month, up by 0.4% on August 2011.
Miles Shipside, Rightmove director and housing market analyst, said: “The Olympics may have focused the nation’s attention on sporting goals in the last month, but for over 120,000 new sellers their goal was to sell their property.
“One would perhaps expect some sellers to have postponed their marketing plans until after the Olympic distractions, though with more working from home it may have given them an opportunity to begin their property move a few weeks earlier in readiness for the hoped-for upturn in buyer activity in the lead up to Christmas.
“The number of new sellers is slightly up on the same period last year, though perhaps as a reflection of their urgency to sell, or to compensate for the distraction of the achievements served up by Team GB, they have dropped their asking prices more aggressively than summer sellers in previous years.”
Rightmove claimed the large monthly fall of 2.4% in new seller asking prices is also a sign of some reticence by estate agents to put property on the market at higher prices, especially when existing stock for sale is failing to attract serious buyer interest.
All regions of the country recorded month-on-month price falls for the first time since November 2011.
Shipside warned: “Estate agents are always aiming to win new seller instructions, but if what’s already on the market isn’t shifting then the best advice they can give to potential new sellers is to undercut those properties already failing to sell.
“With a few more summer sellers around, it seems agents are being a bit blunter on valuations in local markets where summer buyers are scarce.
“With the average time on the market being 92 days, any seller coming to market and hoping to move before Christmas needs to get their skates on to tempt a buyer who can proceed.”
Shipside added that it is possible the Bank of England’s Funding for Lending scheme may lead to greater mortgage availability at more competitive rates which could boost buyer interest.
