Module finance_solution::net_present_value

Net Present Value calculations. Given a series of cashflows, an initial investment (the cashflow at time0), a number of periods such as years, and fixed or varying interest rates, what is the net value of the series of cashflows right now?

For most common usages, we recommend the net_present_value_schedule_solution function, to provide a better debugging experience and additional features. This function allows you to provide varying cashflows and/or varying rates.

For very simple NPV calculations involving a constant cashflow and constant rate, the net_present_value_solution function can be used.

Examples

Simple Usage:

let (rate, periods, initial_investment, cashflow) = (0.034, 3, -1000, 400);
let npv = net_present_value_solution(rate, periods, initial_investment, cashflow);
dbg!(npv.print_table());

outputs to terminal:

period   rate   present_value  future_value  investment_value 
------  ------  -------------  ------------  ---------------- 
0       0.0000    -1_000.0000   -1_000.0000       -1_000.0000 
1       0.0340       386.8472      400.0000         -613.1528 
2       0.0340       374.1269      400.0000         -239.0259 
3       0.0340       361.8248      400.0000          122.7989 

More typical usage (varying cashflows):

let rates = vec![0.034, 0.034, 0.034];
let cashflows = vec![-1000, 300, 400, 500];
let npv = net_present_value_schedule_solution(&rates, &cashflows);
dbg!(npv.print_table());

outputs to terminal:

period   rate   present_value  future_value  investment_value 
------  ------  -------------  ------------  ---------------- 
0       0.0000    -1_000.0000   -1_000.0000       -1_000.0000 
1       0.0340       290.1354      300.0000         -709.8646 
2       0.0340       374.1269      400.0000         -335.7377 
3       0.0340       452.2810      500.0000          116.5433 

Structs

NpvPeriod
NpvSeries
NpvSolution	The custom solution information of a NPV scenario. The struct values are immutable by the user of the library.

Functions

net_present_value	Returns the net present value of a future series of constant cashflows and constant rate, subtracting the initial investment cost. Returns f64.
net_present_value_schedule	Returns the net present value of a schedule of rates and cashflows (can be varying), subtracting the initial investment cost. Returns f64.
net_present_value_schedule_solution	Returns the net present value of a schedule of rates and cashflows (can be varying), subtracting the initial investment cost. Returns a custom solution struct with detailed information and additional functionality.
net_present_value_solution	Returns the net present value of a future series of constant cashflows and constant rate, subtracting the initial investment cost. Returns a solution struct with additional features..