Dividend Reinvestment, How to Calculate Compound Returns Yourself

TL;DR

• Dividend reinvestment means not withdrawing dividends as cash but buying more of the same stock or ETF to seek long-term compound returns.
• This article gives step-by-step calculation methods and Excel/calculator formula examples so you can input your own numbers and see the results.

The basic principle of dividend reinvestment

Dividend reinvestment increases your principal by using paid dividends to buy more of the same asset, which raises future dividend amounts. Over time this can lead to exponential growth, known as compounding. To understand the compound effect you must track each year s dividends and the increased holding quantity after reinvestment.

Items to check before calculating

1. Initial investment amount (example: 10,000,000 KRW).
2. Expected annual dividend yield (example: annual X%). Past yields do not guarantee future results.
3. Dividend payment frequency (annual, quarterly, etc.).
4. Share price movement and fees at reinvestment. Check real trading commissions and trading unit (fractional shares availability).
5. Withholding for dividend income tax and related deductions may change, so confirm current rules with your broker or the tax authority.

Step by step calculation procedure (with examples)

1) Basic annual formula

• Next year holdings = (current holdings) × (1 + dividend yield)
• Holdings after n years = initial amount × (1 + dividend yield)^n

2) For quarterly or semiannual reinvestment

• Update holdings at each payment period using that period s return.
• Example: If 4% annually is distributed evenly quarterly, treat each quarter as about 1% and multiply by (1 + 0.01) each quarter.

3) Reflect share price changes at dividend payment

• Lower share price at reinvestment buys more shares, higher price buys fewer shares, affecting effective returns. For realistic simulation, input the actual share price at each payment date.

Excel-ready formula examples

• Simple annual compounding: =InitialAmount*(1+DividendRate)^Period
• Quarterly reinvestment: =InitialAmount*(1+DividendRate/4)^(Period*4)
• Cashflow simulation (accumulate each quarter s amount): record each quarter s holdings and use it as the next quarter s starting value.

Practical tips and cautions

• Actual results depend on dividend rate, price volatility, fees, taxes and other factors. Tax and regulatory figures can change, so verify with your broker or the tax authority.
• Fractional share trading availability depends on account type and broker. Confirm before assuming fractional purchases are possible.
• To automate the strategy, consider broker automatic reinvestment services or dividend reinvesting ETF share classes. Service terms differ by broker, so check details.

This article is for informational purposes and is not investment advice.