The latest traffic flow report suggests the economy ended last year on a strong note.
ANZ Bank's Truckometer heavy traffic index, which paints a more immediate picture of the economy's health, rose 2.6 percent in December.
The light traffic index, which gives a six-month lead on the economy, rose 1 percent.
ANZ says the data suggests the economy may have grown as much as 1 percent in the December quarter.
