VB.NET Financial Functions Description
DDB Calculates depreciation based on the double-declining balance method (or other specified rate of depreciation).
FV Calculates the future value of an annuity.
Ipmt Calculates the interest payment on an annuity.
IRR Calculates the internal rate of return for a series of transactions.
MIRR Calculates the modified internal rate of return for a series of transactions.
Nper Determines the number of periods for an annuity.
NPV Determines the net present value of an investment.
Pmt Calculates the payment on an annuity.
PPmt Calculates the principal payment on an annuity.
PV Calculates the present value of an annuity.
Rate Determines the interest rate of an annuity.
SLN Calculates the straight-line depreciation of an asset.
SYD Calculates the sum-of-year-digits depreciation of an asset.

Table 1. VB.NET Functions Help C# Make the Grade.
VB.NET financial functions can make your life easier in C#. Don't worry if you don't grasp these right away—MSDN has decent documentation on all these functions in the Visual Basic Language Reference.