Road freight movements have hit a spring pothole, easing off the highs seen a month prior.
The ANZ Bank's Truckometer index for September saw both heavy and light traffic fall.
The heavy traffic index, an indicator of real-time activity, fell 3.3 percent.
Meanwhile, the light traffic index, which pointed to economic activity in the coming months, fell 1.3 percent.
Chief economist Sharon Zollner said while the rate of light traffic eased, it maintained its mild upward trend.
"Given current strong growth in the population via immigration, an upward trend is to be expected," she said.
"However, the data remains considerably more volatile than pre-Covid.
"The light traffic index successfully picked that Q2 GDP wasn't going to be weak, and rightly or wrongly it's suggesting Q3 may have some life in it as well."
Zollner said while heavy traffic data also fell, the measure tended to provide a good steer on manufacturing and production - however, the data was volatile.
"Smoothing through the noise, the three-month average is nothing flash, sending a weaker signal for Q3 than the light traffic is," she said.
"The data reflects that the New Zealand economy is patchy as the cost of living and tighter monetary policy bites."
Despite recent lifts in tourism and a second wind in the housing market, it was unclear how much more the economy would slow, Zollner said.
"It remains unclear whether this overall gentle economic slowdown is going to get more severe - and if not, whether it will be enough to bring inflation sustainably down to target."