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Introduction to the price-to-earnings ratio

Price to Earnings Ratio (or P/E ratio). Created by Sal Khan.

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  • leaf green style avatar for user sam
    Around the 12 minute mark Sal discusses the P/E of a bank account versus a stock, as a means for comparing potential returns. Yet, if there is no dividend, how does a company's earnings translate into a return for the shareholder? It is clear that interest on a bank deposit is earnings that equate to a return, but w/o dividends how does this work for a stock?
    (23 votes)
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    • spunky sam blue style avatar for user Mike Moyle
      In today's world only the most established of companies (the Fortune 500 companies like GE, IBM, Microsoft, etc) pay a dividend. Stocks of non-dividend-paying companies are priced according to the public perception of future value. Their shareholders demand that the company will re-invest their profits (net earnings) wisely, in activities that expand the company's future profits. If the company continues to grow its profits, the stock price will continue to go up. So, because the PE is based on "net earnings" rather than dividends, the PE will adjust itself to the profitability... at least in a rational and fully informed market.

      Many wise investors (Warren Buffet, for instance) will not invest in a company that does not pay a regular dividend. However, paying a dividend is like admitting that you have no lucrative way to expand, that you have reached the limit of your potential, and re-investing in yourself is not the best use of your profits.
      (53 votes)
  • blobby green style avatar for user suiteanswering
    what's a good price to earning ratio?
    (41 votes)
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    • blobby green style avatar for user mcfenn.ur
      There's no "good" P/E, but 10-20 is usually considered fairly valued. <10 is usually considered undervalued and >20 is usually considered overvalued, though it really depends on the industry. Compare the company to its industry peers to determine if its P/E is fair.
      (63 votes)
  • leaf green style avatar for user Adam Twente
    I'm confused about how to calculate the P/E ratio for say Apple. According to his example you would do Price divided by Earnings Per Share.

    His numbers were 3.50/.35 giving a P/E of 10. According to google finance the P/E of Apple is currently 12.99. Apple's stock price is 456.19 and its most recent EPS were 13.87. But 456.19/13.87 gives a PE of 32.9 which is more than double the stated PE. What am I doing wrong?
    (10 votes)
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    • blobby green style avatar for user ritasbook
      If you look on Google finance or Yahoo finance, it says EPS is 35.11. This is the total EPS for all four quarters or in other words EPS for a year. So the P/E= 456.19/35.19= around 13.
      You are just looking at the most recent EPS and that is why you are not getting the correct PE. If you add all the earnings, 13.87 7.05 7.79 6.40 (data from google finance), the total EPS would be $35.11. I am new to this topic too, I hope I answered it correctly.
      (46 votes)
  • blobby green style avatar for user 24ashishjain
    why people says that,"dont believe in P/E " ? Is that a correct statement ?
    (2 votes)
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    • blobby green style avatar for user richjdavies
      It's not quite like "I don't believe in Fairies" -- clearly P/E does it exist. But many people don't think they tell you enough about a company.

      For example Googles P/E is 19... whereas Exxon's is 9.5 and Apple is 15... which is cheaper... only time will tell!
      This is because what investors are willing to pay depends on what they think they will earn in the FUTURE - not what they earn right now. So the fact that Google's P/E is so high suggests that people think they will grow, whereas Exxon's suggest that the market consensus is that it won't grow much at all...
      (17 votes)
  • old spice man green style avatar for user Pat Maloney
    So does the stock price determine market capitalization, or does market capitalization determine the stock price? If stock price determines market capitalization, then who/what exactly determines the stock price?
    (3 votes)
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    • spunky sam blue style avatar for user Mike Moyle
      Market cap is totally determined by share price, and merely gives you an idea how big the company is. Share price is determined by what people are willing to buy or sell the shares for. That willingness is determined by a plethura of factors, many of which are irrational (fear and greed) in the short term. Over the longer term (years) the share price is determined by the company's actual performance, but always impacted on a day-to-day basis by the irrational issues
      (6 votes)
  • blobby green style avatar for user Frank Ichel
    Isn't the E/P ratio known as the Earnings Yield?
    (4 votes)
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  • blobby green style avatar for user Faryl Ury
    He says that the lower the P/E is, the better because you're paying less to get the same. However, later in the video he says that the price could drop from 3,50 to 1.5 and then the P/E would go from 10 to 5, which he says is bad. But I thought that the lower P/E, the better?
    (3 votes)
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  • purple pi purple style avatar for user stickywicket
    The market value is TYPICALLY higher than the book value though, correct? I understand that it can go either way but won't a stocky usually trade up?
    (1 vote)
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    • blobby green style avatar for user kittkatt0
      Yes, the future perceived performance of a company is usually factored into a stock price. Also, intangibles (such as brands or brainpower) may account for a large part of the stock price. For example, when Sergey and Larry founded Google in a garage, they would have near 0 book value, but no one would price Google stock at 0 because it would have been easy to see value in their unique vision and technical ability to achieve it.
      (4 votes)
  • blobby green style avatar for user kanneganti.sairam
    I see there are few companies which have more book value than the market value, so is the market undervaluing them? can we invest in those companies?
    (2 votes)
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  • piceratops ultimate style avatar for user Rayce Wiggins
    How important is P/E when considering which stocks to buy?
    (2 votes)
    Default Khan Academy avatar avatar for user

Video transcript

My son has been successfully subdued, so I think this is a good time to learn about the Price to Earnings ratio. And a lot of times you'll hear people talk about a stock's P/E Ratio. And it's all the same thing. It's just a faster way of saying Price to Earnings ratio. So let's think about the Price to Earnings ratio of the company in question, this widget case study, I guess you could call it, that we've been dealing with. Let's say that the market value-- we talked before that the book value per share of this company is $5. Because the book value of its equity is $5 million. And there's 1 million shares. So 5 million divided by 1 million is $5. But let's say that the market price, let's say that this is Widgets Inc. and let's say that its ticker symbol is WINC, for Widgets Inc. And its price is, it's trading at-- let me make up a good number-- let's say it's trading at $3.50. And then we learned in the first video that a price by itself doesn't tell us a whole lot. So how may shares are there? We know there's a million shares. So the market cap, or what the market perceives the value of this equity is, the market capitalization, is these two numbers. If we have a million shares, then each of them, the market is saying, is worth $3.50, then the equity of the company is worth $3.5 million. And this is the market value of the equity, what the market thinks the equity's worth. So this is interesting. In our case, the book value of the equity was $5 million. But the market is saying, no, no, I don't necessarily believe those accountants. Maybe they're throwing some stuff in here that's not really there. So we say it's only worth $3.5 million. In this case, the company's trading at a discount to its book value. And I won't go into detail on that now, but that's actually a fairly unusual circumstance, unless people are very suspicious about the accounting or the actual book value of the company. Or if they think that this is just a kind of an asset with a useful life that has been shortened. If you owned a bunch of video stores, then all of a sudden you say, I have $10 million of video stores, and then the next day someone makes on-demand videos there, all of a sudden, maybe your assets aren't worth what you thought they were before. But we'll talk a lot more about that when we deal with real examples. But in this case our market cap is below our book value. And you can even look at it from the price. I said the price doesn't tell you much. But it tells you a decent bit if you think of things in per-share. Because we know that the book value per share is $5. The price per share, the market price per share, is $3.50, so you could also say it's trading at a discount to book. Now, what were the earnings of the company? Well it was making $0.35. So let me write this down. Earnings was $350,000 in 2008. And let's just say we're looking this from the vantage point that 2008 has happened. This isn't like I'm at the beginning of 2008 and modeling. So let's say we're looking at this on January 1, 2009. And let's say the company has already released its earnings, although it normally takes a lot longer. Probably closer to 45 to 90 days. But let's say they released their earnings. So we say, oh this company made $350,000 in 2008. Or another thing that you might see a lot when you look at companies, is that this is trailing 12 months earnings. You'll see this TTM sometimes. Because when someone says earnings, are those the earnings last year? Are those the earnings that you're predicting for next year? So this is trailing 12 months earnings. And if you want to look at earnings per share, EPS, is this number divided by the number of shares was $0.35. So first, just to learn what the Price to Earnings ratio is, let's just calculate it. Then we can talk about what it actually means and if we have time, we can have a discussion on why a company might have a higher or lower Price to Earnings Ratio. And that discussion can actually get quite involved. But in this case, you literally just take the price of the stock and you divide it by the earnings per share. So let me switch colors just to ease the monotony. The Price to Earnings ratio is equal to the price-- so $3.50-- divided by the earnings per share. Divided by $0.35. So in this case, the Price to Earnings ratio is 10. What does that tell you? well there's a couple of ways to think about it. One is, you could kind of flip this. No-one ever talks about the Earnings to Price ratio, but that's an interesting thing to even think about. Because it connects it with a lot of other financial concepts that are out there. So this is kind of a Sal special ratio, but it's a useful one to think about. The Earnings to Price ratio is just the inverse of this. 0.35:3.50, which is equal to 1/10. Or 10%. And so the way to think about it is if you're paying $3.50 per share for this company, and let's say the company next year-- so this is trailing 12 months earnings. But let's say this company, for whatever reason, it's a really stable company. It's doing the same thing every year. It's not growing. It's not shrinking. Let's say that not only is this the trailing 12 months earnings, but this is also-- actually, I'll introduce terminology right here. So this is trailing 12 months. You could also have forward earnings. What are forward earnings? You can probably guess. The earnings I just said, this is actually what happened to the company. This was the earnings of the company last year, or the last 12 months. Forward earnings are, you know, there's a bunch of guys with MBAs and CFAs working for the banks, and they write research reports. And they model the company. They meet with the company. They analyze the industry. And if they're good analysts, they'll come up with a number. They'll say, I think this company is not going to change. It's such a super stable business. They're going to make $0.35 in 2009 as well. So in this case, this would be the forward earnings. And usually if it's a well-followed company, there might be 10 or 15 or 20 analysts. And what they do is they average out all of the numbers from all of those analysts. And then if the average is, let's say, $0.35, they'll call this the consensus. So the consensus is just the average of all of the sell side analysts out there. And maybe I should do a whole video on what sell side means, but since I said the word I'll tell you right now. Sell side are like the investment banks and the research houses. And the reason why they're the sell side is because they're always selling you stuff. They're selling you stocks. They're brokering transactions. They write these research reports because they want to go to institutional investors or people who have their brokerage accounts with these banks, and essentially sell them stock. Say hey, you should buy Widgets Inc, because it's only trading at a Price to Earnings of 10. And we really like it. It's much better than buying treasury bonds right now, because you're making more money on it. You're making 10%, and that's just to connect the dots. Price to Earnings of 10. If it's stable, you're making the equity will grow in this coming year by 10%. And that's better than what you get out of treasury bonds. So that's what sell side means. So a sell side analyst is someone who publishes these reports. A buy side analyst is someone who works for a hedge fund or works for Fidelity at a mutual fund. Or works for an endowment or a pension someplace. And they're managing other people's money. And they're trying to figure out if they can believe what's happening. So they're going to do their own analysis. So that's what the buy side is. Those are the people who are actually managing money and deciding what they want to invest the money in. The sell side are the people who do analysis and say, hey due to my analysis isn't this a good stock? Don't you want to buy or sell this stock? So fair enough. That was a bit of a diversion. Anyway, going back to Price to Earnings, we calculated the Price to Earnings. It was 10. But the reason I wanted do to Earnings to Price is because it connects it back to things like yield and interest. I can do a Price to Earnings on my bank account. Let's say in my bank account I have $100. So this is a diversion right here. So let's say I have $100 in my bank account. And over a year I make 2% interest. Let's say it's guaranteed 2%. Maybe it's in the CD. So I have $102 at the end of the year. This 2% were my earnings. So I made $2 of earnings. So the way to think about a bank account is, well how much do I pay for that bank account? Well in this case I paid $100 for the bank account. So the price would be $100. And the earnings on the bank account in that year were $200. So it has a Price to Earnings of 50. Or if you do the Earnings to Price, if you do $2/$100, you get 2%. Which is normally how we think about bank accounts. We say, oh I'm making 2% interest on that bank account. Now, this actually leads to a very interesting question. If a bank account only gives me 2% on my money, and this company is arguably giving me-- assuming that it's stable and I believe the consensus-- it's giving me 10% on the money, why would I even hold this bank account? Why wouldn't I just pour all of my money? Why am I willing to pay a higher Price to Earnings for the bank account than I am for this company? And I think you already get the sense that the lower the Price to Earnings, all else equal-- and that's a big thing-- all else equal, the lower the Price to Earnings, you're paying less for something. You want to have a lower Price to Earnings ratio for the same asset. Because you're getting the same earnings for a lower price. But when you lower the Price to Earnings you are increasing the Earnings to Price. So you would increase your yield. You want to maximize this number. But I'll finish this video with kind of a basic question. Why would someone ever keep their money in the bank at 2% or a Price to Earnings of 50, when they could have a Price to Earnings of 10 with Widgets Inc.? And the answer is because this is very uncertain. Who knows what happens with Widgets Inc.? Maybe all of these guys were-- Maybe this is a big Ponzi scheme. I mean, most companies in this country aren't. And that's another thing to talk about, is country risk. Because even though you're probably suspicious of them now, the US has some of the most transparent companies with some of the best accounting standards. If this was in-- you know, I don't want to state any countries because people all over the world listen to these videos-- but if it were a country with less solid accounting standards, you would be like, they might be making up all of their numbers so I don't trust it. Or you might say, you know, Widgets Inc., even though the analysts are saying that they're going to make $0.35 this coming year, you might say, you know, I don't believe that. I think there's actually a lot of risk in Widgets Inc. That there's actually more volatility here than anyone gives credit for. They might go out of business. There's a strong competitor. There's a lot of risk involved. And the other thing is, even if you don't think there's risk. Even if you think that this company's going to make $0.35 forever, the other reason why you might prefer to have a bank account over Widgets Inc. is because you're guaranteed to get $102 back for your bank account at the end of the year if you wanted. Assuming this is a CD with a one year duration. You're guaranteed to get your $102 back, especially if it's FDIC insured. But in this case, even though the earnings might be the same, something horrible might happen to the markets and everyone just dumps their stocks, money flows just run outside of markets. And for whatever reason people get scared, and the price could go down a lot from $3.50. It could be very, very volatile. And this thing, maybe the price goes from $3.50 to $1.75 a year later. Which it seems like a really good deal, because now the Price to Earnings is $1.75 divided by $0.35, would now be a 5 Price to Earnings. But this could happen. I mean, companies go from a 10 to a 5 Price to Earnings. And then all of a sudden, if you want that money, if you need that money a year later, you've lost half of it. So there's some volatility in the price even though you're assuming that the earnings are stable. So that's a little bit of a taste of why someone might realistically, in this case, pay a higher Price to Earnings for safety. Safety because you know that this earnings stream is guaranteed. And liquidity. Liquidity because you know you're going to get your money back. That you're going to be able to essentially sell your bank account and get cash for it. And you know that it's going to be $100. That there's no volatility in price. Well in this case, you're uncertain about the earnings stream. You're uncertain about what the market will be willing to value it at a year later. And frankly, you might be uncertain about liquidity in general. Maybe this is a really small company and not a lot of people trade in it. And you might not even be able to find anyone to buy it a year later. The epitome of an illiquid asset is maybe a really expensive $20 million house. Even though it might be worth $20 million, a year later you might not-- there are only so many people who can afford a $20 million house. So it's an illiquid asset. Anyway, I want to leave you there. In the next video we'll go into more depth on Price to Earnings ratio, and think about things like growth and stability and whatnot.