Sales excluding autos and auto parts fell by 0.2% from November. Analysts expected sales ex-autos to jump 0.3%.
The December might have been even lower without a stronger-than-expected holiday shopping season. A separate Thursday report from the National Retail Foundation said year-end holiday sales rose unexpectedly by 1.1% to $446.8 billion.
Given that the economy was so weak 12 months ago, the year-to-year increase was strong. December 2009 retail sales jumped 5.4% compared to the same month in 2008.
"[It's not] clear how much of this reflects a catch-up from the fantastically depressed post-Lehman period ... and how much represents a sustainable, if very modest, upturn," said Ian Shepherdson, economist at High-Frequency Economics, in a research note. "We suspect more of the latter."
The December data are not enough "to reach a definitive verdict" on the holiday sales season, Shepherdson said. The January report will be "hugely important" as well because it reflects holiday gift card spending and post-holiday sales.
Total sales for 2009 retreated 6.2% from 2008.
Retail sales leap 1.3% in NovemberLuxury retailer Tiffany raises profit forecast
