Saving 10 baht a day for 20 years contributes 73,000 baht if the calculation uses 365 days per year and excludes leap days. Investing 300 baht per month for 240 months contributes 72,000 baht. The totals differ because the saving schedules use different numbers of days and contribution periods.
This article separates daily saving from a monthly DCA model to show how principal differs from illustrative returns. The embedded video discusses saving 10 baht a day and compound interest; the figures below are calculated from the stated assumptions and formula. They are not presented as results verified from the video.
How much principal does saving 10 baht a day add in 20 years?
10 baht × 365 days × 20 years = 73,000 baht of principal. This excludes any return from depositing or investing the money and excludes leap days. If you instead invest 300 baht per month, the principal is 300 baht × 12 months × 20 years, or 72,000 baht.
How does monthly DCA work?
The Stock Exchange of Thailand describes DCA as investing a fixed amount at regular intervals, such as monthly or quarterly. The method sets the contribution amount for each period; it does not determine whether returns will be positive or meet a goal. Investments still involve risk, and inflation can affect future purchasing power.
For a reproducible comparison, the table assumes a 300 baht investment at the end of each month for 20 years, or 240 contributions. The annual rates are constant hypothetical examples, not forecasts or recommendations to choose an asset expected to earn those returns.
Assumptions and formula
- Invest 300 baht at the end of each month for 240 months; total principal is 72,000 baht.
- Compare hypothetical annual returns of 0%, 4%, and 8%, assumed to remain constant for all 20 years.
- Convert the annual return to an effective monthly rate:
r = (1 + R)^(1/12) − 1. - Fees, taxes, and inflation are not deducted, so these are illustrative future values, not future purchasing power.
The end-of-period value is calculated as FV = PMT × ((1 + r)^n − 1) ÷ r, where PMT is the monthly contribution, r is the monthly rate, and n is the number of periods. At a hypothetical 0% return, the ending value equals principal.
What could 300 baht per month become in 20 years?
| Hypothetical annual return | Total principal | Approximate future value | Monthly contribution to reach 1 million baht* |
|---|---|---|---|
| 0% | 72,000 baht | 72,000 baht | 4,167 baht |
| 4% | 72,000 baht | 109,153 baht | 2,749 baht |
| 8% | 72,000 baht | 170,700 baht | 1,758 baht |
*Monthly contributions are rounded up to the next whole baht to reach the target under the same assumptions. Actual returns may be higher or lower, and losses are possible. An 8% annual assumption does not mean any asset promises that return.
How to use these figures
Saving 10 baht a day can build principal over time. Reaching a 1 million baht target also depends on the amount contributed, the time available, and the risk of the chosen assets. DCA can help structure regular investing; it does not remove asset risk or guarantee returns. Consider fees, taxes, and inflation before using an illustrative projection in a plan.
Sources
- SET e-Learning: definition of DCA
- Stock Exchange of Thailand: expected return
- Stock Exchange of Thailand: investment risk and inflation
Limits of the calculation and video reference
The calculation follows the assumptions shown above and uses SET explanations of DCA, risk, and expected return. The embedded video is a related reference; the article does not independently verify its audio or statements. This is general information, not investment advice.