Considering that the .NET framework is easily on the short list for the most popular business application platform, it is surprising that financial functions are largely ignored. Sure there is a handful of methods squirreled away in VisualBasic.Financial, but most developers don’t even think to look there. It is no wonder companies often turn to Excel.
Excel Financial functions for .NET is a .NET library that provides the full set of financial functions from Excel. The main goal for the library is compatibility with Excel, by providing the same functions, with the same behaviour. Note though that this is not a wrapper over the Excel library; the functions have been re-implemented in managed code so that you do not need to have Excel installed to use this library.
References:
http://www.infoq.com/news/2008/12/FSharp-Financial
http://code.msdn.microsoft.com/FinancialFunctions