Calculating Daily Compound Interest with a Difference

[jazman84]

Hello.

I am calculating Daily compound interest on a Principal from a % p/a rate. I think I may have the right equation, however, I am not 100% confident with the answers.

The principal amount is $20,776.00, the interest rate is 4% p/a, the number of days is 14.

The equation I am using is = $20,776.00*(1+(4%/365))^14 = $20,807.90 I am pretty sure this is right.

However, where things go iffy is when I need to make deposits into the account. The 1st deposit is $43,505.00, this brings the balance to $64,312.90 and is made at the end of the 14 day period and the next is 28 days later. So my next equation look like this:
$64,312.90*(1+(4%/365))^28 =$64,510.53.

This goes on over another 10 months or so with days between deposits changing.

Am I doing this right? If not, how should I be doing it?

Thank you

[Pauleyb]

That looks about right. My suggestion would be to change the exponential number to something like (Date2-Date1) so it will auto-calculate for your different dates.

Pauley

[JustineM]

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