Market researchers at GfK said the mood of consumers in Germany worsened for the third month in a row on Tuesday.
A combination of rising energy prices and the fear of future job losses has led many consumers to save their money, the Nuremberg-based group said, and postpone purchases of big-ticket items such as furniture.
GfK's point-based indicator gave January's consumer climate an estimated score of 3.3 points, down 0.3 points from December.
This bodes badly for 2010, especially since private consumption, which grew by 0.5 percent this year, was one of the redeeming features of the German economy in the aftermath of the financial crisis.
Experts reacted to the figures with some resignation. Joerg Lueschow of the West LB Bank said: "We expected almost exactly these figures from the GfK. But this is almost certainly not the end. We expect the consumer climate to worsen further in the next months."
Other analysts suspected that recent political news had dampened expectations for the new year.
"Sobriety is creeping in amongst consumers," said Sebastian Wanke of Dekabank. "The car-scrapping bonus has run out, the government is more or less stuck in a straitjacket of state debts, and on top of this the growth prognosis for the coming year has been modest.
"The new tax cuts in the Growth Acceleration Law will have some effect on private income expectations, but consumers don't trust it yet," Wanke added.
This year's Christmas shopping figures have defied such dark predictions, however, and GfK researchers are hopeful that the current intense price war among retailers will stimulate consumption.
Editor: Sam Edmonds