New figures show that residential property prices nationwide fell by 17.8% in the year to February, the biggest fall since December 2009.
The Central Statistics Office said this compares with an annual rate of 17.4% in January and a fall of 10.8% in the 12 months to February 2011.
The CSO said that residential prices fell by 2.2% in February, which compares with drops of 1.9% in January and 1.7% the same time last year.
Prices are now 49% lower than their highest level in 2007, the figures show.
The CSO figures show that residential properties in Dublin fell by 1.2% last month and are 20.3% lower than a year ago. Dublin house prices decreased by 0.7% in the month and are 20.2% lower from a year ago, while Dublin apartment prices are 22.9% lower compared with the same time in 2011.
The price of homes in the rest of Ireland fell by 3% in February compared to a fall of 1.5% the same time last year. Prices were 16.4% lower than in February 2011.
The CSO said that house prices in Dublin are 56% lower than their highest level in early 2007, while apartments are 62% lower than they were in February 2007.
Dublin residential property prices are 57% lower than their highest level in February 2007, while the fall in the price of homes in the rest of the country is somewhat lower at 45%.
The residential property price index is designed to measure the change in the average level of prices paid for residential properties sold in Ireland. The index allows for the fact that different types of property are sold at different times.