Sure, you've heard the age-old buy low, sell high, but what does that really mean?

當然，你聽說過 "低買高賣 "這句老話，但它的真正含義是什麼呢？

When is a stock's price considered low? $10 a share? $100? There's no perfect answer to these questions, but there are ways to at least gauge how expensive or cheap a stock is.

股票價格什麼時候算低？每股 10 美元？$100?這些問題都沒有完美的答案，但至少有一些方法可以衡量股票的貴賤。

You see, by using something called a multiple, we can figure out how much we're paying for a stock's underlying business, and if this price has changed over time.

你看，通過使用一種叫做 "倍數 "的東西，我們可以計算出我們為股票的相關業務支付了多少錢，以及這個價格是否隨著時間的推移而發生了變化。

Interested? We'll dive into the topic and more on today's Plain Bagel.

感興趣嗎？我們將在今天的《Plain Bagel》節目中深入探討這個話題以及更多內容。

You may have noticed that when you Google search a stock, like, well, Google for example, you end up with a series of search results, as well as some basic details about the ticker.

你可能已經注意到，當你用谷歌搜索一隻股票時，比如谷歌，你會看到一系列搜索結果，以及股票的一些基本資訊。

In there, you have your stock's open price, market capitalization, and dividend yield, but it also lists something called the P-E ratio of the company.

裡面有股票的開盤價、市值和股息率，還列出了公司的市盈率。

The P-E is an example of what's called a multiple, a ratio that compares a stock's price to some fundamental number. Generally speaking, the higher the multiple, the more expensive a stock is considered. Think of it as like a price per pound at a butcher shop.

P-E 是所謂倍數的一個例子，是一種將股票價格與某個基本數字進行比較的比率。一般來說，倍數越高，股票就越貴。把它想象成肉鋪裡每磅的價格。

In shopping for pork, beef, or chicken, it's difficult to compare the total prices, since the quantity you get is different for each cut. But if you look at the price per pound, you can easily figure out which cut is the best bang for your buck.

在購買豬肉、牛肉或雞肉時，很難比較總價格，因為每種肉的數量不同。但是，如果看一下每磅的價格，您就能很容易地找出哪種肉最划算。

Multiples work in a similar way, allowing us to compare the price of a stock to the underlying fundamentals you get with the purchase. Now, there are hundreds of different multiples that investors can use, including the EV to EBITDA, price to book value, etc, etc.

倍數的作用與此類似，它允許我們將股票價格與購買股票後獲得的基本面進行比較。現在，投資者可以使用數百種不同的倍數，包括市盈率與息稅折舊攤銷前利潤（EBITDA）的比率、價格與賬面價值的比率等等。

Some of the multiples are industry-specific, whereas others are more broad in nature, and each carries a different implication. But the P-E ratio, which stands for the price-to-earnings ratio, is one of the most straightforward and popular.

有些乘數是針對特定行業的，而有些乘數則更為寬泛，每種乘數都有不同的含義。但 P-E 比率（即市盈率）是最直接、最流行的比率之一。

It's easy enough to calculate, since you take the stock's price and divide it by the company's earnings per share. For example, if Plain Bagel Co. had 1 million shares outstanding, each of which were trading at a price of $30, and last year their net income was $2 million, the stock's P-E ratio would be 15 times. This P-E ratio is known as a trailing P-E, because we're calculating it using historical information, and it's one of the easiest multiples to understand. It basically represents how much an investor is willing to pay per dollar of a company's profits. So for Plain Bagel Co., we are paying a price equal to 15 times our share of the company's profit. So the trailing P-E helps conceptualize how much we're paying for a stock, but it does have its shortcomings. The biggest one being that it is backwards-looking, whereas many believe that markets are forward-looking. If a company is expected to release a new product, enter a new market, or improve its operations in the future, then a stock will likely trade higher, something that the trailing P-E wouldn't take into account using past earnings to explain the stock's current price. Because of this, many investors prefer instead to use what's known as a forward multiple, in this case the forward P-E, which divides a stock's price by how much the company is expected to make next year.

計算方法很簡單，用股票價格除以公司每股收益即可。例如，如果 Plain Bagel Co. 有 100 萬股已發行股票，每股交易價格為 30 美元，去年的淨收入為 200 萬美元，那麼該股票的市盈率就是 15 倍。這個市盈率被稱為追蹤市盈率，因為我們是根據歷史資訊來計算的，而且它是最容易理解的倍數之一。它基本上代表了投資者願意為公司的每一美元利潤支付多少錢。是以，對於 Plain Bagel Co.，我們支付的價格相當於公司利潤份額的 15 倍。是以，追蹤市盈率有助於概念化我們為一隻股票支付的價格，但它也

For example, let's say that Plain Bagel Co. is expected to launch a new bagel product next year, and as a result, analysts are expecting earnings to increase to $2.5 million next year.

例如，假設 Plain Bagel Co. 預計明年將推出一款新的百吉餅產品，是以分析師預計明年的盈利將增至 250 萬美元。

In this case, assuming everything else remains unchanged, Plain Bagel Co.'s forward P-E multiple would equal 12 times. Now, the clear problem with forward multiples is that they rely on forecasts, which may not pan out, but they can still help gauge the value of a stock and how much investors are paying up for a company's potential profit. So for Plain Bagel Co., our forward-looking P-E is 12 times. Great, but what does that mean? Well, by itself, not a whole lot. You see, multiples are a relative measure. Sure, understanding how long it will take for your stock to pay for itself is useful, but to understand whether the level is attractive or not, we've got to compare it to other multiples. We could, for example, compare the P-E ratio to Plain Bagel Co.'s historical P-E ratios to see how it has changed over time. This would give us an idea of whether investors are valuing the company higher or lower than normal.

在這種情況下，假設其他一切保持不變，Plain Bagel Co. 的遠期市盈率將等於 12 倍。現在，前瞻性倍數的明顯問題是，它們依賴於預測，而預測可能不會實現，但它們仍然可以幫助衡量股票的價值，以及投資者為公司的潛在利潤付出了多少代價。是以，對於 Plain Bagel Co.，我們的前瞻性市盈率是 12 倍。很好，但這意味著什麼呢？就其本身而言，意義不大。要知道，倍數是一種相對衡量標準。當然，瞭解你的股票需要多長時間才能收回成本是有用的，但要了解這個水準是否具有吸引力，我們必須將其與其他倍數進行比較

If the company's earnings are expected to increase, but the price of the stock has fallen, it would mean that the multiple has contracted, and investors don't value the profitability of the firm as much as they used to. Alternatively, if earnings are falling but the price has risen, well, the multiple has expanded, meaning people are paying more for less profit.

如果預期公司盈利會增加，但股票價格卻下跌了，這就意味著倍數縮小了，投資者不再像以前那樣看重公司的盈利能力。反之，如果盈利下降但股價上升，那麼倍數就擴大了，這意味著人們要為較少的利潤支付更多的錢。

We could also compare the P-E multiple to the stock's long-term average to see whether the margin is larger or smaller than normal. If the stock's 10-year average P-E is 15 times, we could assume that the stock's multiple is temporarily cheaper than normal, and may warrant a buy. If we pick up the stock and the multiple later expands back to its long-term average, then we could earn a return, even if the company's earnings are flat.

我們還可以將 P-E 倍數與該股的長期平均值進行比較，以瞭解差值是大於還是小於正常值。如果該股票的 10 年平均市盈率是 15 倍，我們可以認為該股票的倍數暫時比正常水準便宜，可能值得買入。如果我們買入該股，而該股的市盈率後來又回升到長期平均水平，那麼即使公司盈利持平，我們也能獲得回報。

A key assumption here is that a multiple is expected to revert to its mean over time.

這裡的一個關鍵假設是，隨著時間的推移，倍數有望恢復到其平均值。

And while that doesn't always hold true, investors sometimes look for extreme variations from the mean, with many believing that short-term volatility in a stock's multiple, which could be caused by a bad press release or negative near-term headwind, will eventually subside, causing the multiple to return to its normal level, assuming the company's core business remains unchanged. Awesome, so if I find a company that's trading at a multiple below its historical average, I'm good to buy, right? Well, not quite. Sure, understanding where the company's stock value stands relative to its past is great, but you need to compare the value to other stocks as well, in the same industry. In our analogy, if you found pork on sale for $6 a pound, it may still be too expensive if a butcher down the road is offering pork for a regular price of $2.50 a pound. Similarly, we need to gauge the value of a stock relative to its peers.

雖然這並不總是正確的，但投資者有時會尋找平均值的極端變化，許多人認為，如果公司的核心業務保持不變，那麼股票倍數的短期波動（可能是由糟糕的新聞稿或近期的不利因素引起）最終會消退，導致倍數恢復到正常水準。太棒了，如果我發現一家公司的交易倍數低於其歷史平均水平，我就可以買入了，對嗎？其實不然。當然，瞭解公司股票價值相對於其過去的位置非常重要，但你還需要將其價值與同行業的其他股票進行比較。打個比方，如果你發現豬肉特價每磅 6 美元，但如果路邊一家肉店的豬肉正價每磅 2.50 美元，那你可能還是覺得太貴了。同樣，我

So, let's take Plain Bagel Co. and compare it to Sesame Sands and The Haggle Bagel, which are trading at 4 PEs of 13x and 7x, respectively. If you compare Plain Bagel Co.'s 12x multiple to its peer average of 10x, well, then we can see that the stock is actually more expensive than other bagel companies on average. Alright, so the stock is cheaper than it normally is, but more expensive than its peers, so should I buy or sell or what? Well, as great as it would be to have a one-number basis for making investment decisions, it's simply not that simple.

是以，讓我們拿 Plain Bagel Co. 與芝麻金沙國際娛樂網址（Sesame Sands）和 The Haggle Bagel 進行比較，這兩家金沙國際娛樂網址的市盈率分別為 13 倍和 7 倍。如果將 Plain Bagel Co. 的 12 倍市盈率與同行平均市盈率 10 倍進行比較，那麼我們可以發現，該公司的股價實際上比其他百吉餅公司的平均股價要高。好吧，這隻股票比平時便宜，但比同行貴，那麼我應該買入還是賣出呢？雖然有一個數字作為投資決策的基礎是件好事，但事情根本沒那麼簡單。

Multiples are limited in the amount of insight they provide. With the PE multiple, for example, we aren't taking into account the company's growth rate. Sure, compared to peers, Plain

倍數所提供的洞察力是有限的。以市盈率為例，我們並沒有考慮公司的增長率。當然，與同行相比，平原

Bagel Co.'s PE of 12x may seem expensive, but if Plain Bagel Co. is also growing its earnings at a faster pace, the multiple may be justified. This is why high-growth companies, like those in the tech space, tend to have higher multiples than stocks in slower-moving areas, like utilities.

Bagel Co. 12 倍的市盈率看似昂貴，但如果 Plain Bagel Co. 的盈利增長速度也更快，那麼這個倍數可能是合理的。這就是為什麼科技領域等高增長公司的市盈率往往高於公用事業等低增長領域的股票。

On the other side of the spectrum, just because a company is trading at a PE below its peers, or even below its historical average, doesn't mean it's a good buy. The multiple compression could be justified if the company's fundamentals have deteriorated. What do I mean by that? Well, let's go back to our analogy. Imagine you're at the butcher shop, and you see two steaks trading at $10 a pound and $3 a pound. Looking for some value, you pick up the $3 cut, but when you get home, you find that the steak you bought has expired, and that it's a lower-quality cut, and you're not even sure if it's actually beef anymore. So, aside from learning that there's something wrong with a $3 steak, what's the lesson here? Well, just because something is cheap, doesn't mean you should buy it. A lower stock's PE may reflect a justified devaluation of the company. Maybe for the Plain Bagel Co., keto diets are expected to kill the bagel industry.

另一方面，一家公司的市盈率低於同行，甚至低於歷史平均水平，並不意味著它就是一個好的買點。如果公司的基本面已經惡化，壓縮倍數可能是合理的。我的意思是什麼呢？讓我們回到剛才的比喻。想象一下，你在肉店看到兩塊牛排的價格分別是 10 美元一磅和 3 美元一磅。為了物有所值，你選擇了 3 美元一磅的牛排，但當你回到家時，卻發現你買的牛排已經過期，而且是劣質牛排，你甚至不確定它是否真的是牛肉了。那麼，除了知道 3 美元的牛排有問題之外，這裡還有什麼教訓呢？嗯，便宜的東西並不意味著你就應該買它。較低的股票市盈率可能反映

Or maybe the company is facing regulation that will prevent it from making its staple plain bagel.

又或者，該公司正面臨著法規的限制，無法再製作主打的普通百吉餅。

These are things that would hurt Plain Bagel Co.'s future profitability.

這些都會損害 Plain Bagel Co.

And even though the multiple would contract, it doesn't make the company a good buy.

儘管倍數會縮減，但這並不能使公司成為一個好的買點。

Because the company's core, long-term prospects have deteriorated. That's the thing about multiples.

因為公司的核心、長期前景已經惡化。這就是倍數的問題所在。

They are pretty meaningless without context, and chasing low multiples without an understanding of a company's core business and future prospects may leave you with something called a value trap.

在不瞭解公司核心業務和未來前景的情況下追逐低倍數，可能會陷入所謂的價值陷阱。

A stock that looks cheap compared to its historical prices, but continues to fall even further because of a deterioration in the firm's fundamentals. So, why discuss multiples if they could mean that a stock is both over and undervalued? Well, it's not that multiples are useless.

與歷史價格相比，一隻股票看起來很便宜，但由於公司基本面惡化，股價還會繼續下跌。那麼，如果倍數可能意味著一隻股票既被高估又被低估，為什麼還要討論它們呢？這並不是說倍數毫無用處。

They are a handy way to quickly understand a stock's price level. But, as I said at the beginning, they are a rough gauge of a stock's value at best. Some investors even contest that the PE multiple is incredibly limited because of its use of accounting earnings numbers, which may be easily altered by management assumptions and non-cash items. So, while multiples can certainly help you make investment decisions, you need to ensure that your decision is based on a thorough understanding of a firm's operations and future prospects, not just the stock's multiple. A good approach is to find companies you like based on their fundamentals, and then find some appropriate multiple to understand the firm's valuation after the fact. Looking for cheap stocks first may leave you with a portfolio of low-quality holdings. After all, as Warren Buffett says, it's far better to buy a wonderful company at a fair price than a fair company at a wonderful price. So, next time you find a stock trading at a low multiple or a stake selling at $3 a pound, make sure to check the fundamentals, and the stake's expiration, and that the stake is actually a stake. But, with that said, we're out of time.

它們是快速瞭解股票價格水準的便捷方法。但正如我在開頭所說，它們充其量只是衡量股票價值的一個粗略標準。一些投資者甚至質疑 PE 倍率的侷限性，因為它使用的是會計收益數字，而會計收益數字很容易被管理層的假設和非現金項目所改變。是以，儘管市盈率肯定能幫助你做出投資決策，但你需要確保你的決策是基於對公司營運和未來前景的透徹瞭解，而不僅僅是股票的市盈率。一個好的方法是根據公司的基本面找到你喜歡的公司，然後找到一些合適的倍數，以便在事後瞭解公司的估值。先尋找便宜的股票可能會讓你的投資組合中持有低質量的股票。畢竟，正如

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If you have any feedback or topics you'd like us to cover in future videos, leave a comment down below. For The Plain Bagel, my name is Richard Coffin. Thanks for joining me today.

如果您有任何反饋意見或希望我們在今後的視頻中涉及的話題，請在下方留言。對於《The Plain Bagel》，我的名字是理查德-科芬（Richard Coffin）。感謝您參加今天的節目。