This one:

Sydney’s traffic peaked in 2005 and had been falling steadily ever since.  The number of vehicle kilometres travelled per person has been falling and is now back to 1992 levels

From The Australian – October 4, 2012:

‘Motorway madness to waste billions’ as rail and bus use grows

PUBLIC transport advocates have slammed NSW Premier Barry O’Farrell’s decision to set aside $1.8 billion in funding for a new motorway from Parramatta to Sydney airport, claiming Sydneysiders’ per capita road use is falling amid high petrol prices and increased use of rail and buses.

Gavin Gatenby, the convenor of lobby group Ecotransit, said the NSW government’s support of the WestConnex motorway was “about supporting private vested interests that have sunk billions into building motorways”.

“Per capita road use has been falling for the past eight years in all Australian capital cities, as public transport use has surged. Yet NSW decides to invest billions of dollars in motorways before major public transport projects. It’s sheer madness,” Mr Gatenby said. …

Recent motorway projects in NSW — including the Lane Cove Tunnel, the Cross City Tunnel and the Eastern Distributor — had all failed to reach their forecast traffic numbers. …

Another indication that something profound is going on, with evidence of declining traffic volumes coming in from around the world.  Don’t we need to understand this better before committing to billions of dollars of more road capacity on the assumption that traffic volumes will increase?