How is yahoo finance P/E Ratio TTM calculated?
The correct p/e for bp.l is 5.80. Bp.l is on the London stock exchange and prices are in local currency. The share price of 493 is reported in pence (not dollars). The EPS is reported in pounds. Using .85 pounds = 85 pence, you calculate the EPS as follows: 493.40/85 = 5.80 PE Yahoo totally screwed up. They converted the .85 pounds into US dollars ($1.34) but didn't convert the 493 pence. By using the 493 as dollars, they got 493.9/1.34 = 368 pe! Notice that Yahoo reports the American Depository Shares (symbol 'BP') with an EPS of $8.06. That correctly reflects that there are 6 shares of BP.l per ADS (1.34 * 6 = 8.04). But why is the share price listed at $46.69? Well...  493 GBp (pence) = 4.93 pounds 4.93 pounds  = 7.73 USD 7.73 USD * 6 shares per ADS = 46.38 USD "P/E is Price divided by Earnings Per Share (EPS). P/E TTM is Price divided by the actual EPS earned over the previous 12 months - hence ""Trailing Twelve Month"". In Forward P/E is the ""E"" is the average of analyst expectations for the next year in EPS. Now, as to what's being displayed. Yahoo shows EPS to be 1.34. 493.90/1.34 = P/E of 368.58 Google shows EPS to be 0.85. 493.40/0.85 = P/E of 580.47 (Prices as displayed, respectively) So, by the info that they are themselves displaying, it's Google, not Yahoo, that's displaying the wrong P/E. Note that the P/E it is showing is 5.80 -- a decimal misplacement from 580 Note that CNBC shows the Earnings as 0.85 as well, and correctly show the P/E as 580 http://data.cnbc.com/quotes/BP.L A quick use of a currency calculator reveals a possible reason why EPS is listed differently at yahoo. 0.85 pounds is 1.3318 dollars, currently. So, I think the Yahoo EPS listing is in dollars. A look at the last 4 quarters on CNBC makes that seem reasonable: http://data.cnbc.com/quotes/BP.L/tab/5 those add up to $1.40."
Your observation is mostly right, that 1 is a the number around which this varies.  You are actually referencing PEG, P/E to Growth ratio, which is a common benchmark to use to evaluate a stock. The article I link to provides more discussion. Generally speaking.  1. Take the position size / average daily volume.  2. Multiply that number by 10 or whatever 1/whatever % of volume you think you can execute, ( you can at best acct for 10 percent of traded volume on a day).  3. You now have days until liquidation (x)  4. Take the days until liquidation sample the return over  time x. I.e. if days until liquidation is 10, you would sample 10 day returns.  5. Calculate the distribution characteristics of this window (mean, var, skew, kurt) and calculate VaR based on some confidence.  You can now have a liquidity risk expected loss and a VaR.  If position is on margin don't forget to add the interest cost.  Note: Instead of taking 10 day return, you can take the 10 day VWAP and calculate return between Open and 10 day vwap. Options - yes we can :) Options tickers on Yahoo! Finance will be displayed as per new options   symbology announced by OCC. The basic parts of new option symbol are: Root symbol + Expiration   Year(yy)+ Expiration Month(mm)+ Expiration Day(dd) + Call/Put   Indicator (C or P) + Strike price Ex.: AAPL January 19 2013, Put 615 would be AAPL130119P00615000 http://finance.yahoo.com/q?s=AAPL130119P00615000&ql=1 Futures - yes as well (: Ex.: 6A.M12.E would be 6AM12.CME using Yahoo Finance symbology. (simple as that, try it out) Get your major futures symbols from here: http://quotes.ino.com/exchanges/exchange.html?e=CME I have asked myself this exact same question many times. The analysis would be simple if you invested all your money in a single day, but I did not and therefore I would need to convert your cash transactions into Index fund buys/sells. I got tired of trying to do this using Yahoo's data and excel so I built a website in my spare time. I humbly suggest you try my website out in the hopes that it helps you perform this computation: http://www.amibeatingthemarket.com/ On closer look, it appears that Google Finance relies on the last released 10-k statement (filing date 10/30/2013), but outstanding shares as of last 10-Q statement. Using these forms, you get ($37,037M / 5.989B ) = $6.18 EPS. I think this is good to note, as you can manually calculate a more up to date EPS value than what the majority of investors out there are relying on. "To my knowledge, there's no universal equation, so this could vary by individual/company.   The equation I use (outside of sentiment measurement) is the below - which carries its own risks: This equations assumes two key points: Anything over 1.2 is considered oversold if those two conditions apply.  The reason for the bear market is that that's the time stocks generally go on ""sale"" and if a company has a solid balance sheet, even in a downturn, while their profit may decrease some, a value over 1.2 could indicate the company is oversold. An example of this is Warren Buffett's investment in Wells Fargo in 2009 (around March) when WFC hit approximately 7-9 a share.  Although the banking world was experiencing a crisis, Buffett saw that WFC still had a solid balance sheet, even with a decrease in profit.  The missing logic with many investors was a decrease in profits - if you look at the per capita income figures, Americans lost some income, but not near enough to justify the stock falling 50%+ from its high when evaluating its business and balance sheet.  The market quickly caught this too - within two months, WFC was almost at $30 a share. As an interesting side note on this, WFC now pays $1.20 dividend a year.  A person who bought it at $7 a share is receiving a yield of 17%+ on their $7 a share investment. Still, this equation is not without its risks.  A company may have a solid balance sheet, but end up borrowing more money while losing a ton of profit, which the investor finds out about ad-hoc (seen this happen several times).  Suddenly, what ""appeared"" to be a good sale, turns into a person buying a penny with a dollar.  This is why, to my knowledge, no universal equation applies, as if one did exist, every hedge fund, mutual fund, etc would be using it. One final note: with robotraders becoming more common, I'm not sure we'll see this type of opportunity again.  2009 offered some great deals, but a robotrader could easily be built with the above equation (or a similar one), meaning that as soon as we had that type of environment, all stocks fitting that scenario would be bought, pushing up their PEs.  Some companies might be willing to take an ""all risk"" if they assess that this equation works for more than n% of companies (especially if that n% returns an m% that outweighs the loss).  The only advantage that a small investor might have is that these large companies with robotraders are over-leveraged in bad investments and with a decline, they can't make the good investments until its too late.  Remember, the equation ultimately assumes a person/company has free cash to use it (this was also a problem for many large investment firms in 2009 - they were over-leveraged in bad debt)." The dividend is for a quarter of the year, three months. 80 cents is 3.9% of $20.51. Presumably the Div/yield changes as the stock price changes. On Yahoo, they specify that the yield is based on a particular stated date. So it's only the exact number if the stock trades at the price on that date. Yes, Alpha Vantage. As MasticatedTesticle points out, it is worth asking where it originally comes from, but it looked to me like a solid source for, in particular, intraday trading data. Additionally, Yahoo finance is done on R (zoo, PerformanceAnalytics libraries don't work anymore as far as I can tell). The numbers look right to me tho, let me know if things are off. At this time, Google Finance doesn't support historical return or dividend data, only share prices.  The attributes for mutual funds such as return52 are only available as real-time data, not historical.   Yahoo also does not appear to offer market return data including dividends. For example, the S&P 500 index does not account for dividends--the S&P ^SPXTR index does, but is unavailable through Yahoo Finance. "What you need to do is go to yahoo finance and look at different stock's P/E ratios. You'll quickly see that the stocks can be sorted by this number. It would be an interesting exercise to get an idea of why P/E isn't a fixed number, how certain industries cluster around a certain number, but even this isn't precise. But, it will give you an idea as to why your question has no answer. ""Annual earnings are $1. What is the share price?"" ""Question has no answer""" I think what's screwing up my calculation is the (reL), return on equity levereged figure. The beta for KORS apparently is -0.58, so when I use the formula reL = rf + (ßL)(rm - rf), I get -0.0048 as my reL.   Am I doing my beta wrong? Am I supposed to use a different figure for my beta?    ALSO, further in the process, when using the formula for WACC, my E/(D+E) is essentially 1.0 because market value of equity for KORS is 7bill and its market value of debt is only like 147 million.  edit: I'm beginning to believe that my beta of -0.58 is not rightly used. It's what yahoo told me, but other sources are saying that the beta of KORS is more like -0.01 or close to 0. Yes?   edit 2: Using -0.01 beta, I get a rdWACC of 2.2%. Now this seems more plausible. I did some research on negative betas and found out that they basically don't really exist aside from gold. So Yahoo must be giving me a weird beta figure. Other websites are all giving me -0.01, so I believe that is correct. I understand that ITM have little time value, so they will have small time decay(theta), but why OTM has a lesser theta than ATM? The Time value represents uncertainty.  That uncertainty decreases the farther away from ATM you get (in either direction).  At-the-money, there is roughly a 50% chance that the option expires worthless. As you get deeper in-the-money, the change that is expires worthless decreases, so there is less uncertainty (there is more certainty that the option will pay off).  As you go deeper OTM, the probability that the option expires worthless increases, so there is also less uncertainty. At the TTM decreases, the uncertainty (theta) decreases as well, since there is less time for the option to cross the strike from either direction.  Similarly, as volatility decreases, theta decreases, since low-volatility stocks have a less change of crossing the strike. You could use  the Gordon growth model implied expected return: P = D/(r-g) --&gt; r = D/P (forward dividend yield) + g (expected dividend growth). But obviously there is no such thing as a good market return proxy. "the ""how"" all depends on your level of computer savvy. Are you an Excel spreadsheet user or can you write in programming languages such as python? Either approach have math functions that make the calculation of ROI and Volatility trivial. If you're a python coder, then look up ""pandas"" (http://pandas.pydata.org/) - it handles a lot of the book-keeping and downloading of end of day equities data. With a dozen lines of code, you can compute ROI and volatility." There are many ways to calculate the return, and every way will give you a different results in terms of a percentage-value. One way to always get something meaningful - count the cash. You had 977 (+ 31) and in the end you have 1.370, which means you have earned 363 dollars. But what is your return in terms of percentage? One way to look at it, is by pretending that it is a fund in which you invest 1 dollar. What is the fund worth in the beginning and in the end? The tricky part in your example is, you injected new capital into the equation. Initially you invested 977 dollars which later, in the second period became worth 1.473. You then sold off 200 shares for 950 dollars. Remember your portfolio is still worth 1.473, split between 950 in cash and 523 in Shares. So far so good - still easy to calculate return (1.473 / 977 -1 = 50.8% return). Now you buy share for 981 dollars, but you only had 950 in cash? We now need to consider 2 scenarios. Either you (or someone else) injected 31 dollars into the fund - or you actually had the 31 dollars in the fund to begin with. If you already had the cash in the fund to begin with, your initial investment is 1.008 and not 977 (977 in shares and 31 in cash). In the end the value of the fund is 1.370, which means your return is 1.370 / 1.007 = 36%. Consider if the 31 dollars was paid in to the fund by someone other than you. You will then need to recalculate how much you each own of the fund. Just before the injection, the fund was worth 950 in cash and 387 in stock (310 - 200 = 110 x 3.54) = 1.339 dollars - then 31 dollars are injected, bringing the value of the fund up to 1.370. The ownership of the fund is split with 1.339 / 1.370 = 97.8% of the value for the old capital and 2.2% for the new capital. If the value of the fund was to change from here, you could calculate the return for each investor individually by applying their share of the funds value respective to their investment. Because the value of the fund has not changed since the last period (bullet 3), the return on the original investment is (977 / 1.339 - 1 = 37.2%) and the return on the new capital is (31 / 31 = 0%). If you (and not someone else) injected the 31 dollar into the fund, you will need to calculate the weight of each share of capital in each period and get the average return for each period to get to a total return. In this specific case you will still get 37.2% return - but it gets even more comlex for each time you inject new capital.