Interest Amortization Table

Within the sector of finance is an arena of borrowing because using other people’s money is how regular folks start in gigantic business.

Borrowing is also how folks who don’t occur to have $400,000 at their disposal purchase nice new homes in nice neighborhoods. Without mortgages, very few people would own homes and the middle class would not exist, as there would be two classes of people, the house owners and people who leased from them.

The most vital part of borrowing is understanding how much money you are paying back to the lender and how much cash you are wasting on interest. Central to this knowledge is the understanding of what an interest amortization table is and the way to use it.

In this article not only will we discuss these two things, but also you will really be taught the way to build an interest amortization table and we intend to work out one as we are going along.

What will the table tell us?

The first step to working out an interest amortization table is the understanding of what the table will tell us. In short, amortization tables break regular payments into two parts, the principal paid and the interest paid. So, it would behoove us if we knew what the total regular payment was to begin with.

I know, it potentially sounds like a cop out as we could work out the payment, but that part of the equation will get left for another article. Here, we’re going to go to a monetary or mortgage calculator and find out the payment. Then, we’ll do the calculations to destroy the payment down into its two parts.

Let’s start by employing an example. In this example, the numbers may sound peculiar but we’re going to use numbers which will make the example easy to follow. So, shall we say we have a mortgage with a principle of $360,000. The mortgage will be paid off over thirty years, or 360 monthly payments. The interest rate will will be a 1970’s type 12%.

Interest calculation formula

Now, we will see how much interest we will pay on the first payment. First we are going to take the amount of principal we have left to pay. In this case it is going to be the whole mortgage of $360,000. We need to divide it by the amount of months we have left to pay as we are building a monthly amortization table. This will tell us the amount we are paying interest on for one month.

Next, we wish to multiply this amount by one month’s interest. One month’s interest will be found by dividing the annual rate of interest rate by twelve. Then we’ve got to multiply this amount by the amount of months left to pay on the mortgage, in this example 360. If we didn’t do this, we might just be seeing the amount of interest that is paid if there were only one month left to pay the mortgage.

Simplify the formula

Here’s how that formula looks: Int. On month’s payment=principal left/ number of months left x monthly interest x number of months left. Now, if you study the formula you’ll see the term “number of months left” twice. Once it’s a numerator (above the line ) and once it’s a denominator (below the line). This implies we are able to divide it by itself. So, the formula now looks like : Int. On month’s payment=principal left x monthly interest. Pretty simple, huh!

Begin calculating

Now, let’s build our interest amortization table. $360,000 x .01= $3,600. This is the interest paid the first month. Uncertain where the .01 came from? It is 12%, or .12, which is the yearly interest rate divided divided by twelve giving us the monthly interest rate.

Next, we take the monthly payment we got from a mortgage calculator, which is $3,703.01, and we know the interest on the first payment is $3,600 so we may take away it from $3,703.01, which will let us the principal part of the first payment is $103.01. This is the first entry in our amortization table. $3,6000 interest and $103.01 principal.

At this point, we know we no longer owe $360,000 on the mortgage as we have paid $103.01, so the principal left is now $360,000 - $103.01, or $359,896.99. We now multiply this number by .01 to get the interest part of the second payment. This is $3,598.97 and, since we know the total payment is $3,703.01, we will subtract $3,598.97 from it to get $104.04 which is the principal paid on the second payment.

There you have it. You just continue figuring out in this manner for another 358 payments and you’ll have built your amortization table absolutely by hand. This, in reality, is something few folk can say!

Even if you do not continue on making these calculations, you now know, from a very inside perspective, exactly what amortization is all about!