Skip to main content

Compounding interest formula

Money grows exponentially with the compounding of interests!

Just imagine, you put in $2,000 in a bank account which has a fixed interest rate of 3% and when the interest on this $2,000 has accrued at the end of the year, instead of taking out the interest, you plough back this interest of $60 to the $2,000 that you have placed at the beginning of the earlier year to reap an even bigger interest.

Thus, at the beginning of the second year, you would have $2,060 in your account for the interest to effect on in the second year, and so on subsequently.

I have provided below a useful formula for the calculation of the amount one can receive in the nth year due to such compounding of interest:

Amount received in nth year= {(1+ rate of compound interest) to the power of n} multiply by starting amount put in Year 1, e.g. if interest rate is 15%, rate of compound interest = 0.15)

There is another form of compounding of interest rate. Say you put $300 every month into a bank deposit and at the end of every year; there will be an x % of interest earned on the amount accumulated at the end of each year. Instead of taking out this interest, you keep this interest earned so that the interest earned on the 2nd year will be on the amount you have accumulated over the past two years together with the interest.

It will be clearer with an example.

Assume you put in $300 per month into a bank account with a compound interest of 15%. At the end of the first year, you would have $3,600 and with the 15% interest earned on this amount you would have $4140. Similarly, at the end of the second year, you would have amassed ($4,140 +$3,600) x 1.15= $8,901

Let x =monthly amount put in the account
n = number of years
y = interest rate (e.g. if interest rate is 15%, y= 0.15)

The general calculation would be as follows:

1) 12 multiply by x multiply by (1+y)
2) Divide the result obtained in 1) by y
3) Calculate (1+y) to the power of n, then minus 1 from this result
4) Multiply the result obtained in 2) with that obtained in 3) to obtain the amount amassed at the end of nth year due to the compounding of interest.

Comments

Popular posts from this blog

Vernon Leong Jun Wei

What happens to the 31 year old bride groom, Vernon Leong Jun Wei? As the news of this latest unnatural and bizzare death developed, it seemed that Vernon did not jump from the 24th storey of Hilton Hotel as was believed earlier. There were 3 video camera footages which might prove otherwises for the cause of Vernon's death. The first video footage showed Vernon at the 24th storey, making his way hurriedly into the fire escape staircase. The next video footage showed Vernon at the 2nd storey which also holds some shops and the final footage showed an unconscious Vernon motionless at the ground of the hotel. Vernon was cladded casually in a T-shirt and pants and have left his hotel room while his wife was taking a shower. It seemed that he might be escaping from something or somebody or that he might be chasing after something or somebody. What did Vernon see and experience at his last moments? The police is still investigating the case. It is really a very tragical and sad

Kampong Lorong Buangkok

Amidst the blazing afternoon sun today, my Dear and I made our way to Kampong Lorong Buangkok. The visit was a timely one as there is such a high buzz being generated over the last kampong in modern Singapore. After alighting from Bus 854 from Eunos, it was not difficult to find our way to the kampong. The entrance of the kampong was distinct as you could see from the picture: the 'ulu-ness' (rural charm) is evident from the attap-roofed buildings and more unkempt conditions. A signboard with hand-written text welcome my Dear and I to the last kampong in Singapore: As we entered the kampong, I spotted a middle-aged woman talking to an old man. I had seen the old woman before on TV. She was none other than the owner of the kampong land. In the documentary, I learnt that the whole kampong land was passed to her by her late father. She has kept the land and have not gone on to sell the land to the government. If she were to sell the land, she would be an instant multi-millionair

Performance Bonus

It is the time of the year civil servants receive their performance bonuses (PBs). In the coming two weeks, civil servants will not only receive their performance bonuses, special ‘growth bonuses’, would also await them for the very first time. These PBs and growth bonuses are only applicable to performers, defined as officers with assessed performance gradings above the ‘D’ grade. Typically, civil servants receive their performance bonuses in March, a 0.5 month of bonus in July and a 13th month plus AVC in December. Are all the bonuses good? To be frank, the bonuses dished out in Civil Service are averages at best. With the various bonuses being given out in these months: July, December and March, a civil servant who would like to quit would most likely try to find a ‘suitable’ month to quit so as not to forfeit his bonuses. The December bonus is generally the most generous portion. To quantify for this bonus, an officer would have to be in service till the end of January ne