Home
Search
 
What's New
Index
Books
Links
Q & A
Newsletter
Banners
 
Feedback
Tip Jar
 
C# Helper...
 
XML RSS Feed
Follow VBHelper on Twitter
 
 
 
MSDN Visual Basic Community
 
 
 
 
 
TitleCalculate compound interest over time in Visual Basic .NET
DescriptionThis example shows how to calculate compound interest over time in Visual Basic .NET.
KeywordsWindows Forms programming,example program,calculate compound interest,interest,example,Visual Basic .NET, VB.NET
CategoriesAlgorithms
 
Enter the principle amount, interest rate, and number of years in the textboxes. When you click Calculate, the program uses the following code to display your balance for the following years.
 
Private Sub btnCalculate_Click(ByVal sender As _
    System.Object, ByVal e As System.EventArgs) Handles _
    btnCalculate.Click
    lstBalances.Items.Clear()

    Dim principle As Double = Val(txtPrinciple.Text)
    Dim interest_rate As Double = Val(txtInterestRate.Text)
    Dim num_years As Integer = Val(txtYears.Text)

    For i As Integer = 1 To num_years
        Dim current_value As Double = _
            principle * (1 + interest_rate) ^ i
        lstBalances.Items.Add(i & ": " & _
            vbTab & FormatCurrency(current_value))
    Next i
End Sub
 
The program simply loops through the years, evaluating the compound interest formula:

    balance = principle * Math.Pow(1 + interestRate, i)

Interesting tidbit: To estimate how long it will take to double your money, you can use the "Rule of 72." Divide the interest rate into 72 and the result tells you roughly how many years it will take to double your money. For example, at 7.2% it'll take about 10 years. It's a pretty decent estimate.

 
 
Copyright © 1997-2010 Rocky Mountain Computer Consulting, Inc.   All rights reserved.
  Updated