This is the largest contraction in economic activity recorded since quarterly records began.
The figures show that activity in the building and construction sector was down overall by 18.4%.
However, this masks a contraction of 33% in the building of new housing.
The figures also show that investment in the economy overall was down by almost 15% during the year.
However the manufacturing sector bucked the trend in the economy, with output up by 4.3% as a result of a strong performance by multi-national companies based here.
The figures also confirm that the economy has now contracted for a second consecutive quarter, which is considered by economists to be the technical definition of a recession.
However the CSO figures relate to the period before the collapse of the massive US financial institution Lehman Brothers in September and the consequent meltdown in global financial markets.
As a result, analysts are expecting the economic trends will worsen in the months ahead.
