Apparently it was in large part, according to this WSJ article. The piece tells readers that Ireland's economy shrank by 2.3 percent from the third to the fourth quarter, meaning that it dropped at a 9.2 percent annual rate, to use the normal terminology of people in the United States when talking about growth data. However the article later tells us that the story is not as bad as it first appears, since much of this decline is due to a major drug going off patent, which has reduced the income flows recorded in Ireland.
Due to its low corporate tax rate, many multinational companies book income in Ireland even though it was actually generated elsewhere. These phantom income flows have little to do with the state of the Irish economy. To avoid this problem it is more useful to look at gross national income. If we look at the OECD data on Irish national income we find that the number for 2012 (the most recent year available) was still 8.6 percent below the 2008 level. In fact, it was 2.3 percent below the 2005 level. Obviously Ireland is yet another one of those great success stories from the economic whizzes at the European Commission.