myCalculator

Kevin Stanford
28 Feb 2016

Overview

This calculator allows the user to compare up to three different potential vehicle purchases to see how price, tax and interest rates, and payback period affect:

  • Monthly Payment
  • Total Loan Amount

Payback Period Selector

The slider tool allows the user to select payback period of 12 to 60 months in six-month increments.

payback period slider

Payment Amount Calculation

Payment amount is calculated using the pmt() function in library FinCal

library(FinCal)

pmt((3.9/100)/12   # Annual Percentage Rate 
                    # divided by 12 for 
                    # monthly payments
    ,60            # Payback period (months)
    ,28000         # Amount to be financed
    ,0.0           # Amount due at end of
                    # payback period -- 
                    # 0 indicates completely
                    # paid off
)

[1] -514.4

Payment Plan Comparison

Plot visualizes payments for each vehicle option over the enitre length of the payback period.

plot