Windows XP lost nearly one per cent of global market share during August, according to both Netmarketshare and StatCounter, but there's not been a corresponding bounce in the prevalence of other Microsoft operating systems.

The Reg has been tracking the two OS-counters for 11 months now and during that time Netmarketshare has tracked Windows XP from 31.24 per cent to 23.89 per cent of detectable PCs online. Statcounter started with a lower number – 21.28 per cent – and has charted a slower decline to 14.29 per cent.

This month, both outfits show a bump in Windows 8.1 use. Netmarketshare records it going from 6.56 per cent to 7.09 per cent while Statcounter records a jump from 7.45 per cent to 8.25 per cent. At a guess, the rises could reflect business PC fleet refreshes conducted during the northern summer when staff numbers thin out, and perhaps also some back-to-school PC purchases.

Here's Netmarketshare's data from October 2013 to August 2014.

Oct 2013 Nov 2013 Dec 2013 Jan 14 Feb 14 Mar 14 Apr 14 May 14 June 14 July 14 August 14 XP 31.24 31.22 28.98 29.23 29.53 27.69 26.29 25.27 25.31 24.82 23.89 Vista 3.63 3.57 3.61 3.3 3.1 2.99 2.89 2.9 2.95 3.05 3.02 Win 7 46.42 46.64 47.52 47.49 47.31 48.77 49.27 50.06 50.55 51.22 51.21 Win 8 7.53 6.66 6.89 6.63 6.38 6.41 6.36 6.29 5.93 5.92 6.28 Win 8.1 1.72 2.64 3.6 3.95 4.1 4.89 5.88 6.35 6.61 6.56 7.09

And here's Statcounter over the same period.

Oct 13 Nov 13 Dec 13 Jan 14 Feb 14 Mar 14 Apr 14 May 14 Jun 14 Jul 14 Aug 14 XP 21.28 20.53 19.79 19.21 18.57 18.61 17.16 16.17 16.3 15.15 14.29 Vista 5.62 5.16 4.3 3.97 3.79 3.67 3.57 3.52 3.37 3.52 3.32 Win 7 54.89 55.13 54.8 54.32 55.2 54.68 55.11 55.06 55.03 55.33 55.67 Win 8 8.15 8 8.13 7.93 7.91 7.85 7.81 7.61 7.57 7.51 7.33 Win 8.1 0.32 1.18 2.22 3.19 3.87 4.48 5.24 6.17 6.7 7.45 8.25

Graphics? You say you want graphics? How about the one below, which averages the two OS-counters' data and plots it as a line graph?

Netmarketshare and Stacounter's data averaged, and plotted

Conclusions? XP has a rump of users in no hurry to move, Windows 8.1 is slowly taking market share but there are enough Windows 7 buyers out there to keep its market share more-or-less steady even though the overall pool of Windows users increases. That means there's a hard core of folks – probably businesses – that Microsoft just can't shift to Windows 8. ®