Microsoft’s Windows operating system continued its slow decent in September as Apple’s Mac OS and Google’s Android platform again showed gains. Advertising network Chitika’s research division, Chitika Insights, published an infographic on Monday outlining operating system usage share on its network in the month of September. After losing nearly three-quarters of a point last month, Windows again dipped 0.592% to land at 77.7% for the month of September. The Windows OS has now dropped a total of 1.35% since July. Apple’s OS X platform showed the biggest gains in the month, jumping 1.039% to hit double digits at 10.6%. Google’s Android OS gained marginally in September to reach 3.3%, and Apple’s iOS dipped to 5.2%, shedding 0.301% of its usage share as the world waits for the iPhone 5 to launch next month. Chitika’s full infographic follows below.