The 17 member nations of the euro common currency union, dragged down by the flagging economies of Greece, Portugal, Spain and Ireland, saw factory activity decrease more than expected in December, the statistical office of the European Union announced Tuesday.

Factory output for December decreased by two percent when compared to the previous year, Eurostat noted, more than the one percent decline economists expected. The slowdown was unevenly distributed, with energy production -- down 11.9 percent when compared to 2011 -- leading the plunge.

Factories in Greece and Portugal, where stringent austerity measures have led to decreased economic activity and civil unrest, fared the worst. Output in those countries was down 12.4 percent and 8.9 percent, respectively. Germany, the Eurozone's top economy, saw output decline 0.7 percent, while France, the second-largest economy, fared worse than the average, with a decline in factory production of 2.2 percent.

Interestingly, Netherlands and Luxembourg, which are not seen as troubled Eurozone economies, fared badly, down 6.6 percent and 9.6 percent, respectively. Belgium, whose economy is closely tied to those two countries, did not report numbers.

The Eurozone factor output numbers will likely serve as a reminder that the euro area is re-entering recession, economists at Deutsche Bank wrote in a research note following the release.

The numbers are likely to tamp some of the optimism that arose at the beginning of the month, after industrial purchasing managers worldwide reported higher orders than economists predicted. Those surveys showed purchasing managers were more optimistic about the economy in both December and January, something that was expected to temper the industrial slowdown.

Eurostat numbers also showed something of a decoupling in December between the fate of Eurozone states and that of the 10 other EU member states that do not use the euro. While the United Kingdom, the leading economy among those non-euro states that is following a self-imposed austerity plan, saw industrial production decline 2.7 percent, other nations actually did better than in January of last year.

The Nordic states improved as did certain Eastern European countries. Poland, for example, saw factory output grow at an outstanding 10 percent.