The index fell in seven of 16 countries monitored by the Conference Board. Inflation rates rose in four countries and were unchanged in five, the research firm said.
In the 28-member European Union, the harmonized inflation index held steady, but in the 18-member eurozone, which shares the euro as currency, the index was "down very slightly," the Conference Board said.
The harmonized index in the eurozone, a weighed average of inflation rates, indicates relatively tame pricing in the eurozone, "but this masks significant divergences," the Conference Board said.
In Austria, for example, inflation rose from 1.2 percent to 2 percent. Prices also rose in Belgium and the Netherlands but higher inflation in smaller countries was offset somewhat by the 1.2 percent rate in Germany, the region's largest economy.
Year-on-year U.S. inflation stood at 1.2 percent in December, up from 0.3 percent in November. In Japan, inflation was steady at 1.9 percent in December after eight consecutive months of rising prices.
Inflation came in higher than 1.5 percent in four of the 16 countries including Austria and Britain, each with a rate of 2 percent, Japan with a rate of 1.9 percent and Norway with a 1.8 percent inflation rate.