ANZ's Truckometer indicator fell last month, suggesting little momentum in the economy as the year ended.
The heavy traffic index tracks truck movements on 11 roads which historically have been well correlated with gross domestic product.
It fell 5.4 per cent last month, reversing gains in October and November.
ANZ chief economist Cameron Bagrie said the indicator had flagged the economy's softness in the September quarter and now suggested only modest improvement in the December quarter.
"We are left with the overarching impression of an economy where the clearest trend is still the lack of one," he said. "Monthly volatility is to be expected across indicators such as the Truckometer.
"However, the degree of volatility also seems to fit well with the general impression of an economy moving in fits and starts."
An uncertain global scene, the high New Zealand dollar and a soft labour market made anaemic growth quite understandable.
However, the failure of growing positives like the rebuilding of Christchurch and improving housing market to flow through to the broader economy was perhaps more telling, Bagrie said.
Various sentiment surveys, including this week's quarterly survey of business opinion from the New Zealand Institute of Economic Research, offered hope.
"But timely real-time data such as our Truckometer flags caution."