Our browser stats post is late this month. The source we normally use, Net Market Share, has changed the way it reports its data. This is good and bad. Mostly good, but it took extra time to retrieve the data and then decide what to do with it.

The good part is that we now have separate statistics for mobile browsers and desktop browsers. This answers long-standing demands to break this information out to take a closer look at that small but increasingly important market. The bad part is that the new figures are much harder to compare to historic ones; Net Market Share has completely separated mobile usage from desktop usage.

So, for example, while Internet Explorer was last month reported as having 52.81 percent of the total market, it's this month being reported as having 55.31 percent of the desktop market, and essentially none of the mobile market. Safari, in contrast, has gone from 8.05 percent of the total market to 4.64 percent of the desktop market, and 52.99 percent of the mobile market.

We tend to prefer Net Market Share's data because the company strives to account for sampling bias in its figures. A common problem for those collecting browser usage statistics is that the sample base used often favors sites hosted in the US or EU, and with user bases that similarly favor those countries. Sites and users in Asia, in contrast, tend to be under-represented.

Browser usage is known to show quite marked national variations, so a stat tracker that predominantly surveys US and EU users will not give an accurate representation of usage in significant markets such as China. Net Market Share attempts to correct for this sampling bias by scaling its numbers according to the size of the Internet-using population in each country. This makes its figures more representative of global trends, but makes the company's numbers essentially unique; other stat trackers don't apply similar scaling. As a result, we're beholden to the decisions Net Market Share makes.

The result of all this is that our graphs and numerical comparisons aren't especially comparable with those from previous months. So we'll have some graphs for this month and point out some broad trends, and hopefully things will get back to normal next month.

Though the new data in some ways strengthens Internet Explorer's position by demonstrating that its hold on the desktop market is, at 55 percent, stronger than previously indicated, the overall trend remains the same; its share is dropping. Chrome, in contrast, is continuing to make gains. Firefox continues to hover at around the 22-23 percent level.

Mobile usage is dominated by Safari, with more than half of all users using Apple's browser. Though Android sales have overtaken iPhone sales, the Android browser is down in third place, trailing behind Opera Mini. Overall, the mobile market is still small, with just 6.4 percent of Web users using mobile browsers.

The upgrade graphs show that Firefox is still splitting its user base between those who've followed the rapid release policy, and those who've stuck with 3.6. The transition from 4 to 5 to 6 appears to be going reasonably smoothly—though not as rapidly as Chrome's similar moves—but many Firefox users appear content to stick with 3.6. Until Firefox addresses certain issues with its rapid release process—incompatibility issues with some add-ons, and a lack of automatic updates—it's likely that many of these users will continue to prefer 3.6.





Chrome users are continuing to upgrade quickly and automatically, and Internet Explorer's chart shows Microsoft's continued struggle to get users onto the latest and greatest version of its software.

Meanwhile, here at Ars, Chrome is continuing to gain against Firefox. If current trends continue, the Mozilla browser will be overtaken before the year is out.