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Let's say you have an investment balance of $100,000, and you want to know how long it will take to get it to $200,000 without adding any more funds. With an estimated annual return of 7%, you'd divide 72 by 7 to see that your investment will double every **10.29 years**.

The rule says that to find the number of years required to double your money at a given interest rate, you just divide the interest rate into 72. For example, if you want to know how long it will take to double your money at eight percent interest, divide 8 into 72 and get **9 years**.

So, if the interest rate is 6%, you would divide 72 by 6 to get 12. This means that the investment will take about **12 years** to double with a 6% fixed annual interest rate.

If you want to double your money in five years, divide 72 by five. According to the Rule of 72, it would take about **14.4 years** to double your money at 5% per year.

Given a 10% annual rate of return, how long will it take for your money to double? Take 72 and divide it by 10 and you get 7.2. This means, at a 10% fixed annual rate of return, your money doubles every **7 years**.

It takes **9.9 years** for money to double if invested at 7% continuous interest.

We saw in the previous section that investing in the S&P 500 has historically allowed investors to **double their money about every six or seven years**. Your initial $1,000 investment will grow to $2,000 by year 7, $4,000 by year 14, and $6,000 by year 18.

Do you know the Rule of 72? It's an easy way to calculate just how long it's going to take for your money to double. Just **take the number 72 and divide it by the interest rate you hope to earn**. That number gives you the approximate number of years it will take for your investment to double.

The Rule of 69 is **used to estimate the amount of time it will take for an investment to double, assuming continuously compounded interest**. The calculation is to divide 69 by the rate of return for an investment and then add 0.35 to the result.

The Rule of 72 is a simplified formula that calculates how long it'll take for an investment to double in value, based on its rate of return. The Rule of 72 applies to compounded interest rates and is **reasonably accurate for interest rates that fall in the range of 6% and 10%**.

The 4% rule is a rule of thumb that suggests retirees can safely withdraw the amount equal to 4 percent of their savings during the year they retire and then adjust for inflation each subsequent year for 30 years. The 4% rule is a simple rule of thumb as opposed to a hard and fast rule for retirement income.

“The longer you can stay invested in something, the more opportunity you have for that investment to appreciate,” he said. Assuming a 7 percent average annual return, **it will take a little more than 10 years for a $60,000 401k balance to compound so it doubles in size**. Learn the basics of how compound interest works.

The Rule of 72 is **a calculation that estimates the number of years it takes to double your money at a specified rate of return**. If, for example, your account earns 4 percent, divide 72 by 4 to get the number of years it will take for your money to double. In this case, 18 years.

One of those tools is known as the Rule 72. For example, let's say you have saved $50,000 and your 401(k) holdings historically has a rate of return of 8%. 72 divided by 8 equals **9 years** until your investment is estimated to double to $100,000.

The annual percentage yield on 6% compounded monthly would be 6.168%. Using 6.168% in the doubling time formula would return the same result of **11.58 years**.

Example: How long will it take our money to triple in a bank account with an annual interest rate of 8.45% compounded annually? Answer: **Approximately 13.5 years** to triple. Make a note that doubling or tripling time is independent of the principal.

Senator Elizabeth Warren popularized the so-called "50/20/30 budget rule" (sometimes labeled "50-30-20") in her book, All Your Worth: The Ultimate Lifetime Money Plan. The basic rule is to **divide up after-tax income and allocate it to spend: 50% on needs, 30% on wants, and socking away 20% to savings**.

The 10% rule **encourages you to save at least 10% of your income before taxes and expenses**. Calculating the 10% savings rule is a simple equation: divide your gross earnings by 10. The money you save can help build a retirement account, establish an emergency fund, or go toward a down payment on a mortgage.

- Invest in Stocks for the Long-Term. ...
- Invest in Stocks for the Short-Term. ...
- Real Estate. ...
- Investing in Fine Art. ...
- Starting Your Own Business (Or Investing in Small Ones) ...
- Investing in Wine. ...
- Peer-to-Peer Lending. ...
- Invest in REITs.

Warren Buffett once said, “The first rule of an investment is **don't lose [money]**. And the second rule of an investment is don't forget the first rule.

This marketing principle is a maxim that was developed in the 1930s by the movie industry, who found through research that **a potential moviegoer had to see a movie poster at least seven times before they would go to the theatre to see a movie**.

1 Expert Answer

Using our calculator we will find that it takes about **20.4895 days** to quadruple the money invested under 7% interest rate compounded daily.