Oil futures ended the week with a loss of more than 6% on Friday, with U.S. prices little changed for the session. Traders continued to fret over the outlook for energy demand, as well as a weekly increase in U.S. crude supplies, which raised the potential for an oversupplied market. October West Texas Intermediate oil rose 3 cents, or 0.08%, to settle at $37.33 a barrel on the New York Mercantile Exchange. Prices for the front-month contract lost 6.1% for the week, according to Dow Jones Market Data.Market Pulse Stories are Rapid-fire, short news bursts on stocks and markets as they move. Visit MarketWatch.com for more information on this news.