Crude oil prices trod water for the week as uncertainty about demand continued to weigh on the market. Prices were down slightly, with the benchmark West Texas Intermediate settling on Friday at $81.24 a barrel, compared with $81.50 a week ago. Not even relatively bullish forecasts for oil demand, such as the International Energy Agency's report on Friday raising its forecast by 70,000 barrels a day for 2010, or the decline in the dollar could propel oil prices forward.