Microsoft announced on Monday that it has sold 400 million Windows 7 licenses to date, but that hasn’t stopped the tech giant’s share of the global operating system market from sliding. According to market watcher Net Applications’ data for June 2011, Microsoft’s global operating system market share slid to 88.29% as it continued on its slow but steady decline. The second most popular OS in the world was Apple’s OS X, which was up a nominal amount to 5.37% of the global OS market, followed by iOS with 2.63%, Java ME with 1.12% and Linux with 0.95%. Though Android devices continue to sell rapidly, Net Applications placed the OS in the No. 6 spot in June with 0.72% of the global market.Â Since January of this year, Apple’s OS X and iOS market shares have risen steadily while Windows continues to slide.Â According to Net Applications’ revised data, Windows’ OS share dropped below 90% in January of this year for the first time since it climbed above the threshold. It had been reported earlier that the OS slid under 90% last November, but Net Applications has since updated its figures to show that Windows held a 90.81% share in November 2010 and a 90.29% share in December. Two charts showcasing Net Applications’ June data follow below.