U.S. stock futures rose as better-than-forecast jobs growth and a drop in the unemployment rate bolstered optimism in the world’s largest economy. Equity futures extended gains as U.S. employers added more workers to payrolls than forecast in December. The 200,000 increase followed a revised 100,000 gain in November that was smaller than initially estimated, Labor Department figures showed in Washington. The median forecast was 155,000. The unemployment rate unexpectedly fell to 8.5 percent, the lowest since February 2009, while hours worked and earnings climbed.