Michael VanDaniker has created an interesting visualization of web traffic to W3Schools.com using a soon-to-be-released visualization product called Axiis.
Each of the concentric rings are essentially pie charts showing the percentage of visitors using each browser for a particular time slice, starting with January 2002 in the center and working out to August 2009. The numbers on W3schools.com don’t quite add up to 100% because they don’t report on browsers that make up less than 0.5% of their visitors. This results in a gap at the end of each ring.
In the chart, Blue is IE, Orange is FireFox, Green is first Netscape then Chrome, Grey is Safari, and red is Opera. It’s fully interactive, hovering over any bar gives the actual percentage number. However, it still suffers from the same problem of almost all circular charts, it’s difficult to compare the lines. With the high density of the chart, you can get a “feel” for trends (like FireFox grows fast, as does Chrome), but actual comparisons are difficult.
Visualizing Historic Browser Statistics with Axiis. via CoolInfographics
Good article.