How DO I Calculate Compound Interest?

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ArchiOffice Online handles the computation of compound interest. It calculates the compound interest based on the formula:

 

A = P * ( 1 + r/n )(n * t)

 

where

 

A =

Total Amount (including interest)

P =

Principal Amount (the initial amount borrowed or deposited)

r =

Annual Rate of Interest

n =

Number of times the interest is compounded in a year

t =

Time (period for which an amount is deposited or borrowed)

 

You can understand the calculation of compound interest in ArchiOffice Online from this example:

 

1. Select a project and specify the Compound Interest Term and Rate on the Projects > Billing > Options screen.

 

 

2. Create an invoice for this project with invoice amount $10 and invoice date 02/02/2016 and then finalize it.

 

 

3. Create another invoice with an invoice amount $0 (for easier calculation) and date as

07/27/2016.

 

 

Here is the calculation of compound interest for these two invoices: $10 and $0.49.

 

Calculation

 

For the invoice of $10:

 

Paid Amount = $0

Unpaid amount= $10

Balance = $10

 

Interest Term = 30 (set at project level)

 

Interest Rate = 10% (set at project level)

 

First invoice date = 02/02/2016

 

Second invoice date = 07/27/2016

 

Number of days between 02/02/2016 and 07/27/2016 =  176

 

P = Balance = 10

t = 175/365 = 0.482191780

n= 365/Interest Term = 365/30 = 12.1666666

r = Interest Rate/100 = 10/100 = 0.1

 

According to the formula,

 

A = P * ( 1 + r/n )(n * t)

   = 10 * (1 + 0.1/12.1666)(12.1666 * 0.4821)

   = 10 * (1.00821)5.8655

   = 10.49127

 

As A is the total amount including interest,

 

Compound Interest = A - P

                          = 10.49127-10

                          = 0.49