Right now the Annuity class isn't well-equipped to handle general accumulation functions. See Vaaler & Daniel textbook example 3.3.12 where the interest rate changes from .06 to .05. The shortcut formulas are only valid when the compound interest rate does not change.
Right now the Annuity class isn't well-equipped to handle general accumulation functions. See Vaaler & Daniel textbook example 3.3.12 where the interest rate changes from .06 to .05. The shortcut formulas are only valid when the compound interest rate does not change.