Compounding interest - Savings.

Soldato
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Random question but does anyone know how to calculate the increase in value of say, £200 a month over 10 years compounded? I used to be able to work it out in Excel but I seem to have forgotten. :o
 
First cell = 200
2nd cell = First Cell * 1.05 (assume 5% interest)
3rd cell = 2nd cell * 1.05
Copy and past for as many years as you want.
 
200 * (1 + (annual interest rate in percent / 1200)) ^ 120

Edit, thats for a starting value of £200 with interest compounded monthly. Is that what you want?
 
First cell = 200
2nd cell = First Cell * 1.05 (assume 5% interest)
3rd cell = 2nd cell * 1.05
Copy and past for as many years as you want.

that would be a one off saving.

edit 3.

Ok I have woken up.

200 per month
year 1 = 2400
year 2 = (year1*1.05) + (2400)
Year 3 = (year2*1.05) + (2400)

so on so on.

10 years =
30K

assuming 200 every month. and assuming 5% every year, paid yearly.
 
Last edited:
200 * (1 + (annual interest rate in percent / 1200)) ^ 120

Edit, thats for a starting value of £200 with interest compounded monthly. Is that what you want?

I'm after the compounded value of £200 a month, every month, paid into the savings account.
 
that would be a one off saving.

edit 3.

Ok I have woken up.

200 per month
year 1 = 2400
year 2 = (year1*1.05) + (2400)
Year 3 = (year2*1.05) + (2400)

so on so on.

10 years =
30K

assuming 200 every month. and assuming 5% every year, paid yearly.

Although it won't't make much difference, doesn't that assume that one payment of £2400 is paid in at the beginning of the year and 5% interest paid on that entire amount? Rather than interest being paid on £200, then £400 (plus 200/0.05), then £600(plus...) etc?
 
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