Both of ANZ's Truckometer indexes rose in May, suggesting economic growth is picking up.
"All very well, but meaningless if businesses are not paying their bills by due date. It's not good out there at the moment."
ANZ's index of vehicle movements suggests a slight pick up in GDP for Q4, but the start to 2013 is not looking so positive.
The monthly analysis of vehicle movement data shows the economy is moving in "fits and starts".
Despite a bounce in October and November in annual growth terms, traffic volumes suggest the economy has lost momentum in recent months.
The latest ANZ analysis of vehicle movements suggests annual growth has slowed.
A 5.3% fall in the heavy traffic index took the indicator to its lowest level in more than a year and contrasts the gains of the previous two months.
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