The ANZ Truckometer heavy traffic index and the light traffic index both fell in December.
Figures show heavy traffic fell by 4.2% and light traffic by 1.7% for the month.
ANZ Chief Economist Sharon Zollner says there a “positive signals” for fourth-quarter GDP growth despite the decline.
This is due to earlier market strength, she says.
“However, the light traffic index is giving a mildly softer signal for growth in mid-2018, with the three-month average level of the index dipping a smidgen for the first time since late 2014.
“Political uncertainty, a cooling housing market, tighter credit availability and transitioning growth drivers could cause a growth hiccup in the near term.
“However, the still-strong upward trend in the light traffic index, despite the small dip, suggests this economy still has plenty of momentum,” Zollner says.
