Statistics Canada said lower prices for chemical products "largely offset gains elsewhere, including an advance in petroleum and coal products."
The Raw Materials Price Index was higher, gaining 3.8 percent in December, largely due to higher prices for crude oil, the agency said.
Statistics Canada said prices in 10 out of 21 major commodity groups rose, while eight dropped and three were unchanged.
Petroleum and coal prices rose 0.7 percent, while prices for lumber and wood products rose 1.2 percent. Meat, fish and dairy prices rose 0.9 percent pushed by a 1.8 percent gain in meat prices alone.
Conversely, chemical product prices fell 1.4 percent and prices for primary metal products dropped 0.6 percent pushed by a 2.7 percent decline in prices for aluminum products.