.NET Version Penetration
If you develop a .NET application it’s a good idea to know how many people have Microsoft .NET Framework installed on their PCs.
I found poor information about .NET version penetration, but This post helped me a lot.
| March 2008 | June 2009 | August 2009 | October 2009 | |
| Dot Nothing | 28.12% | 25.6% | 25.53% | 21.4% |
| .NET 1.0 | 2.59% | 0.6% | 0.4% | 0.3% |
| .NET 1.1 | 23.22% | 13.0% | 8.41% | 7.7% |
| .NET 2.0 | 27.41% | 23.2% | 23.02% | 11.6% |
| .NET 3.0 | 17.67% | 14.4% | 10.01% | 6.3% |
| .NET 3.5 | 0.99% | 21.82% | 32.63% | 52.7% |
The bad news is that only 52.7% of the users has .NET Framework 3.5 installed on their PCs, but as you can see from the table they become more and more very fast 
P.S. The latest information about .NET version penetration was for October 2009, if you found newer I’ll be very thankful to post a link to it as a comment and I’ll update the table above.
