Portugal's Gross Domestic Product dropped to its lowest level in 15 years during the third quarter of 2008 due to the global financial crisis, according to reports published Friday.

The National Institute of Statistics of Portugal (INE) said the GDP registered a drop of 2.5 percent in the third quarter of 2008 to the lowest level since the first quarter of 1993.

Portugal's economy has been affected by the crisis because it is largely dependent on exports to countries like Spain and Germany that already have entered recession.

However, the INE said the two GDPs cannot be directly compared because the GDP for the third quarter of 2008 was calculated under a different accounting system than was used in 1993.