Buying of Electronic Arts Inc's Madden NFL '07 (Xbox 360), +2.78 DKP (+1.78%), shares accelerated following the release of December sales figures that built on the strong November numbers. Shares had been rising since early November when the stock traded in the mid-60s. Since December 21, the stock has risen 55.9% from 99.99 DKP to 155.86 DKP. The stock price has appreciated significantly with higher trading volume on the simExchange and sales figures that confirmed the Xbox 360 edition’s success. The stock rose another 6.97% yesterday.