Compounding Interest Formulas for Varying Annual Deposits and Interest Rates

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To calculate compounding interest for varying annual deposits and interest rates, start with an initial amount, such as $1,000, and add a fixed deposit, like $10,000, annually for a specified period. Use Excel to set up the first cell with the initial amount, and subsequent cells with the interest formula that references the previous cell as the principal while adding the annual deposit. This method allows for easy adjustments to the interest rate and deposit amounts. For a scenario involving consistent annual deposits over ten years, the same formula structure applies, ensuring compounding occurs at the same rate. This approach effectively models investment growth over time.
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I think I found a simple formula if I was putting in the same amount of money each year, but what if I wanted to start with 1000$, add 10k$ for 10 years, and then watch it compound at X interest; how would i set that up?

And if you know, can you put this formula into Excell.
 
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Eph said:
I think I found a simple formula if I was putting in the same amount of money each year, but what if I wanted to start with 1000$, add 10k$ for 10 years, and then watch it compound at X interest; how would i set that up?

It's very easy to do with Excel -- just have the first cell with the starting amount, then for each cell below it have the interest formula beneath, referring to the cell above as principle, and add in the amount you deposit each year.
 
What about if you want to just put in a deposit of say 10k per annum for 10 years but have it still compound at the same yearly rate?
 
Eph said:
What about if you want to just put in a deposit of say 10k per annum for 10 years but have it still compound at the same yearly rate?

Yep, just like I said. Follow the instructions above.
 
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