The economies of the 30 member nations of the Organization for Economic Cooperation and Development (OECD) grew by an average of 2.9 per cent in 2004 over the preceding year, the Paris-based group said Tuesday. Of the 30 member states, the United States showed the strongest growth, with GDP expanding by 3.9 per cent in 2004, and Germany's economy was the weakest, growing only by 0.6 per cent, the OECD said in a statement. For the fourth quarter of last year, the OECD region showed a rise in GDP of 0.6 per cent on average compared to the preceding quarter. This figure included three countries with negative growth for the quarter: Italy, Germany and Japan.