If there's one thing you want to be sure of when it comes to investing and retirement planning, it's that you'll have enough money to meet your financial needs over the long-term.
當你考慮到投資和退休計劃時,有一件事是你想要知道的,那就是你是否有足夠的錢去滿足你的長期財務需求。

Part of retirement planning and investing involves making calculations to see how likely--and how quickly--your money is to grow over time. Compound interest is an amazing thing, and the Rule of 72 is a simple way to quickly estimate how long it will take your investment to double in size, assuming you reinvest any dividends. It's a helpful way to put the time value of money into perspective as you map your retirement and investing strategies.
投資和退休計劃的一個環節就是去計算你的財富的未來增值,是漲是跌、是快是慢。復利是一個神奇的東西。你的投資需要多長時間才能翻番?72法則是快速估計所需時間最簡單的方法(假設你所有的利息也再投入到投資中)。當你在規劃退休計劃和投資戰略時,它是一個計算貨幣的時間價值的有效工具。

Another upside is that utilizing this rule is relatively simple. The only piece of information you need to complete the Rule of 72 calculation is the annual rate of return on your investment. Although, you'll probably also want to use a calculator to run the numbers.
使用72法則也非常的簡單,你唯一需要的數據就是投資的年回報率。當然,你還是希望用計算器去跑數據。

One thing to note: the Rule of 72 works best for investments that have a fixed rate of return. While most investments don’t have a fixed rate of return over a long period of time, you can use an average estimate to get a pretty good idea of how long it will take you to double your money.
有一點需要注意:對于有固定收益率的投資,72法則才最好使。然而大多數的投資并沒有長期固定收益率,不過你可以用平均收益率來代替,這樣也能算出你的投資多久才能翻番。

 

How to Use the Rule of 72
如何使用72法則?

If you're ready to put the Rule of 72 to work, here's what to do. To estimate how long it takes for your money to double, simply divide 72 by the interest rate. The result is how many years it will take for your money to double at that rate.
如果你打算開始使用72法則,這是你需要做的。想要簡單地預測投資本金何時翻番,你只需要用72除于收益率即可。結果就是該收益率下你的本金翻番所需要的時間。

For example, let’s assume you can earn a 6% rate of return. How long will it take $1,000 to grow into $2,000? Here's the equation:
舉個例子,比如投資回報率是6%,需要多長時間1000美元的本金才能變成2000美元呢,等式在此:

72 / 6 = 12 years
72 / 6 = 12 年

In this example, if you invested $1,000 into an account that earned a flat 6% annual rate of return, after 12 years, your investment would be worth around $2,000.
在這個例子中,你投資1000美元,固定收益率是6%,在12年后,你將擁有2000美元。

That's a simple way to calculate earnings but it can be powerful for determining whether there's a gap or potential shortfall in your savings strategy. The Rule of 72 can help you gauge whether your current savings plan is sufficient for reaching your short- and/or long-term goals.
雖然72法則只是一個簡單計算投資收益的方法,但它更大的價值是計算出同一筆錢用來投資和用于儲蓄之間的利差是多少。72法則能幫你判定你當前的儲蓄計劃能否達到你的短期或長期目標。

 

The Rule of 72 by Interest Rate
收益率72法則

Since interest rates can vary, the Rule of 72 calculation can produce different results, based on what you've invested in. To save you a little time, here are some common interest rates, plus the amount of time it will take for you to double your investment with each interest rate:
雖然收益率各有不同,但72法則能根據收益率得出不同的結果。為了節省你的時間,這里是常用的收益率和對應的本金翻番所需時間。

1% - 72 years
2% - 36 years
3% - 24 years
4% - 18 years
5% - 14 years
6% - 12 years
7% - 10.3 years
8% - 9.0 years
9% - 8.0 years
10% - 7.2 years
11% - 6.5 years
12% - 6.0 years
1% - 72 年
2% - 36 年
3% - 24 年
4% - 18年
5% - 14年
6% - 12年
7% - 10.3年
8% - 9.0年
9% - 8.0年
10% - 7.2年
11% - 6.5年
12% - 6.0年

 

Remember, It’s Just an Estimate
記住,它只是一個估計

Keep in mind that this is just a quick estimate. Depending on changes in the rate of return over time, what you’re invested in, how you invest it, how interest is applied, and possible tax implications, the actual amount of time needed to double your money will vary.
記住,這只是一個快速估計。收益率、本金數量、投資方式、計息方式、稅務影響,這些因素都會影響72法則得出的結果。

Even so, the rule of 72 can be helpful when you quickly want to compare the rate of growth of two investments. You can easily see at a glance which one is likely to yield a better rate of return to decide where the best place is to allocate your money.
雖然如此,當你想快速比較兩筆投資時,72法則還是很有效。你可以一眼看出哪筆投資的收益最好,這樣你可以決定如何配置你的錢。

The rule of 72 also works in reverse — it can be helpful in understanding the power of inflation. If you consider the average long-term rate of inflation is between 3% and 4%, you’ll notice when you use the rule of 72 that something worth $100 today will cost $200 in about 20 years.
72法則也有別的用法,它可以讓你很好理解通貨膨脹的力量。如果長期通貨膨脹率在3%到4%之間,使用72法則后,你就會發現,現在價值100美元的東西在20年后需要200美元去購買。

This can help illustrate the power of inflation, which can have a significant impact on your retirement strategy. And, the Rule of 72 is also useful in realizing a rate of return over time that can not only overcome inflation, but also taxes, which can take a bite out of your investments and retirement income.
這可以說明通貨膨脹的重要性,它會對你的退休計劃有重大影響。還有,通貨膨脹和稅收能大程度稀釋你的投資本金和退休收入,而72法則能幫你找到那個能戰勝通貨膨脹和稅收的投資回報率。

 

翻譯:老李