Oil prices fell sharply on Friday as U.S. retail sales in March shrank by the biggest margin in nine months. U.S. retail sales in March unexpectedly dropped 0.4 percent to a seasonally adjusted 418.3 billion U.S. dollars, following a 1 percent gain in February, the Department of Commerce reported Friday. Meanwhile, U.S. consumer confidence plunged to a 9-month low in April, the Thomson Reuters/University of Michigan index of consumer sentiment revealed. Consumer spending accounts for about 70 percent of total U.S. economic activity. A decline in retail sales is a troubling sign for the overall economy, as traders worried that the U.S. economy may end the first quarter on softer footing. Oil market was also rocked by the downgraded forecast. The International Energy Agency, the Organization of Petroleum Exporting Countries and the Energy Information Administration all cut their forecasts for 2013 global oil demand this week. Light, sweet crude for May delivery lost 2.22 dollars, or 2.37 percent, to settle at 91.29 dollars a barrel on the New York Mercantile Exchange. Brent crude for May delivery was down 1.16 dollars, or 1.11 percent, to close at 103.11 dollars a barrel.