Request TVM formula guidance

[iMatt04bit]

Ran a test using the scenarios listed on page 17 of MathSand and results look good.
Using the full compliment of logarithms.
I cut the number of pre-guess selections down to 6 of the best ones.
Different TVM scenarios will call for the best choice, which is usually the Dieter formula.

Dieter I have to ask: how did you determine that formula? Its awesome.
2 * (PV + N * PMT + FV) / (FV * (2*K-1.0+N) + PV * (2*K-1.0-N))

I'll post results.

-matt