finance 0.1.0
The fundamental package for financial computing with Dart.
This package provides a set of highlevel functions and classes that make it easy to compute financial ratios, patterned after spreadsheet computations. It's platformindependent, supports iOS and Android.
Using #
The easiest way to use this library is via the toplevel functions. They allow you to make financial calculations with minimal hassle:
Future Value calculation #
What is the future value after 30 years of saving $1000 now, with an additional monthly savings of $100. Assume the interest rate is 7% (annually) compounded monthly?
print(Finance.fv(rate: 0.07 / 12, nper: 30 * 12, pmt: 100, pv: 1000));
Thus, saving $1000 today and then $100 a month at 7% annual interest leads to $130,113.59 available to spend in 30 years from now.
Payments calculation #
What is the monthly payment needed to pay off a $100,000 loan in 10 years at an annual interest rate of 2.5%?
print(Finance.pmt(rate: 0.025 / 12, nper: 10 * 12, pv: 100000));
Thus, in order to payoff (i.e., have a futurevalue of 0) the $100,000 obtained today, a monthly payment of $942.69 would be required. Note that this example illustrates usage of future value having a default value of 0.
Number of period calculation #
If we only had $500/month to pay towards the loan, how long would it take to payoff a loan of $100,000 at 3% annual interest?
print(Finance.nper(rate: 0.03 / 12, pmt: 500, pv: 10000));
So, over 20 months would be required to pay off the loan.
Principal and Interest payment calculation #
What is the amortization schedule for a 1 year loan of $5000 at 10% interest per year compounded monthly? And the total interest payments?
final Iterable<Map<String, num>> payments =
List<int>.generate(12, (int index) => index + 1).map((int per) =>
<String, num>{
'per': per,
'pmt': Finance.pmt(rate: 0.1 / 12, nper: 1 * 12, pv: 5000),
'ppmt':
Finance.ppmt(rate: 0.1 / 12, per: per, nper: 1 * 12, pv: 5000),
'ipmt':
Finance.ipmt(rate: 0.1 / 12, per: per, nper: 1 * 12, pv: 5000),
});
payments.forEach(print);
final num interestPaid =
payments.fold(0, (num p, Map<String, num> c) => p + c['ipmt']);
print(interestPaid);
Thus, the total interest paid are close to $275.
Present Value calculation #
What is the present value (e.g., the initial investment) of an investment that needs to total $20,000 after 10 years of saving $100 every month? Assume the interest rate is 7% (annually) compounded monthly.
print(Finance.pv(rate: 0.05 / 12, nper: 10 * 12, pmt: 100, fv: 15692.93));
So, to end up with $20,000 in 10 years saving $100 a month at 7% annual interest, one's initial deposit should be $1,339.28.
Interest rate calculation #
What is the interest rate for a $8,000 loan if the loan term is 5 years and and payments are $152.50 monthly?
print(Finance.rate(nper: 60, pmt: 152.5, pv: 8000, fv: 0));
The calculated interest rate is 0.45% monthly, or 5.42% annually.
Net present value calculation #
What is the Net Present Value of an investment that requires $15000 deposit now and then makes the following withdrawals at regular (fixed) intervals: 1500, 2500, 3500, 4500, 6000?. Assuming the ending value is 0 and a discount rate of 5%.
print(Finance.npv(rate: 0.05, values: <num>[15000, 1500, 2500, 3500, 4500, 6000]));
So, this investment is worth $122.894 today.
Internal Rate of Return calculation #
What is the Internal Rate of return of an investment that requires $15000 deposit now and then makes the following withdrawals at regular (fixed) intervals: 1500, 2500, 3500, 4500, 6000?. Assuming the ending value is 0.
print(Finance.irr(rate: 0.05, values: <num>[15000, 1500, 2500, 3500, 4500, 6000]));
So, the IRR of this investment is 5.24%.
[0.1.0]  3/9/19 #
 Added nper, ppmt, ipmt, pv, rate, npv and irr. Stibilize interfaces
[0.0.5]  2/9/19 #
 Extracted quote retrieval to finance_quote package. Added fv and pmt functions.
[0.0.4]  1/9/19 #
 Documentation fixes.
[0.0.3]  1/9/19 #
 Documentation fixes.
[0.0.2]  1/9/19 #
 Documentation fixes.
[0.0.1]  1/9/19 #
 Initial implementation of finance plugin.
import 'package:finance/finance.dart';
void main(List<String> arguments) {
// What is the future value after 30 years of saving $1000 now, with
// an additional monthly savings of $100. Assume the interest rate is
// 7% (annually) compounded monthly?
print(Finance.fv(rate: 0.07 / 12, nper: 30 * 12, pmt: 100, pv: 1000));
// What is the monthly payment needed to pay off a $100,000 loan in 10
// years at an annual interest rate of 2.5%?
print(Finance.pmt(rate: 0.025 / 12, nper: 10 * 12, pv: 100000));
// If you only had $500/month to pay towards the loan, how long would it take
// to payoff a loan of $10,000 at 3% annual interest?
print(Finance.nper(rate: 0.03 / 12, pmt: 500, pv: 10000));
// What is the amortization schedule for a 1 year loan of $5000 at 10%
// interest per year compounded monthly?
final Iterable<Map<String, num>> payments =
List<int>.generate(12, (int index) => index + 1).map((int per) =>
<String, num>{
'per': per,
'pmt': Finance.pmt(rate: 0.1 / 12, nper: 1 * 12, pv: 5000),
'ppmt':
Finance.ppmt(rate: 0.1 / 12, per: per, nper: 1 * 12, pv: 5000),
'ipmt':
Finance.ipmt(rate: 0.1 / 12, per: per, nper: 1 * 12, pv: 5000),
});
payments.forEach(print);
final num interestPaid =
payments.fold(0, (num p, Map<String, num> c) => p + c['ipmt']);
print(interestPaid);
// What is the present value (e.g., the initial investment) of an investment that
// needs to total $20000 after 10 years of saving $100 every month? Assume the
// interest rate is 7% (annually) compounded monthly.
print(Finance.pv(rate: 0.07 / 12, nper: 10 * 12, pmt: 100, fv: 20000));
// What is the interest rate for a $8,000 loan if the loan term is 5 years and
// and payments are $152.50 monthly?
print(Finance.rate(nper: 60, pmt: 152.5, pv: 8000, fv: 0));
// What is the Internal Rate of return of an investment that requires $15000 deposit now
// and then makes the following withdrawals at regular (fixed)
// intervals: 1500, 2500, 3500, 4500, 6000?. Assuming the ending value is 0.
print(Finance.irr(values: <num>[15000, 1500, 2500, 3500, 4500, 6000]));
// What is the Net Present Value of an investment that requires $15000 deposit now
// and then makes the following withdrawals at regular (fixed)
// intervals: 1500, 2500, 3500, 4500, 6000?. Assuming the ending value is 0
// and a discount rate of 5%.
print(Finance.npv(
rate: 0.05, values: <num>[15000, 1500, 2500, 3500, 4500, 6000]));
}
Use this package as a library
1. Depend on it
Add this to your package's pubspec.yaml file:
dependencies:
finance: ^0.1.0
2. Install it
You can install packages from the command line:
with pub:
$ pub get
with Flutter:
$ flutter pub get
Alternatively, your editor might support pub get
or flutter pub get
.
Check the docs for your editor to learn more.
3. Import it
Now in your Dart code, you can use:
import 'package:finance/finance.dart';
Popularity:
Describes how popular the package is relative to other packages.
[more]

76

Health:
Code health derived from static analysis.
[more]

100

Maintenance:
Reflects how tidy and uptodate the package is.
[more]

98

Overall:
Weighted score of the above.
[more]

87

We analyzed this package on Apr 8, 2020, and provided a score, details, and suggestions below. Analysis was completed with status completed using:
 Dart: 2.7.1
 pana: 0.13.6
Maintenance suggestions
The package description is too short. (2 points)
Add more detail to the description
field of pubspec.yaml
. Use 60 to 180 characters to describe the package, what it does, and its target use case.