Today i had to calculate 99th percentile and slope and forecast. I was hoping .net may have something or i should be able to get some open source, but after couple of hours of search i was not able to find anything.
I decided to write my own component and got some java pseudo-code using koders.com and wrote one, here is VB.net code to compute nth percentile, i was too lazy to go back and study statistics literature and client gave me the logic for slope and forecast calculation. (Thanks Terry!)
PS: During this process, we figured out the percentile calculation in Excel is not statistically accurate.
Update 2/10/07: Let me share some of the common code i wrote in last few months. Unlike Microsoft enterprise library or application blocks these were written with some assumptions and simplicity in mind, so don't expect this to be feature rich. If you find any bug/issue with code leave a note. Compressed file has a data access layer component, common routines used for web and desktop, authorization component for web; all code written in .net 2.0