Why does Yahoo Finance list the 10y T note (TNX) at 1/10 of CBOE and Google Finance?
"The CBOE states, in an investor's guide to Interest Rate Options: The Options’ Underlying Values   Underlying values for the option contracts are   10 times the underlying Treasury yields (rates)—   13-week T-bill yield (for IRX), 5-year T-note   yield (for FVX), 10-year T-note yield (for TNX)   and 30-year T-bond yield (for TYX). The Yahoo! rate listed is the actual Treasury yield; the Google Finance and CBOE rates reflect the 10 times value.  I don't think there's a specific advantage to ""being contrary"", more likely it's a mistake, or just different."
"I mean, I'd say ""no shit"". The model is easy to reproduce (see the inverse model proposed by CHX and the new NYSE American), and people don't have a real incentive to trade there. IEX's main selling point to the buy side was the reduced price impact order router, which ultimately went away when they became an exchange.  Listings could be interesting, but I can't see why any company that doesn't have some sort of statement to make would want to list there versus the big two, or BATS. Hell, even BATS, a much more established market, has had a hard time drawing listings.  I'm glad they've seen a small bump in market share in the last few months, but I can't see them becoming one of the big three players any time soon (especially after having shat all over the industry during their launch period).  Side note: The UTP SIP (and soon the CTA SIP) are both **much** faster than when IEX went live. Turns out inside updates via the SIP are received faster than the prop market data feed, and faster than updates received over an order entry connection. Under these circumstances the street knows a trade occurred before the participants in the trade. This information asymmetry often results in market makers getting run the hell over, and makes them less likely to quote at the inside on your market." The official source for the Dow Jones P/E is Dow Jones.  Unfortunately, the P/E is behind a pay-wall and not included in the free registration. The easiest (but only approximate) solution is to track against an equivalent ETF.  Here's  a list of popular indexes with an equivalent ETF. Source A few days ago they launched Fannie Mae Guaranteed Multifamily Structures (link) but who knows?  It's a penny stock now. Google Finance is pretty good at marking news right on the chart for a particular stock.  That's how I tracked that piece of news down.  Can't say that it precipitated a lot of people buying the stock, but Google Finance isn't a bad place to start looking. Try Google Finance Screener ; you will be able to filter for NASDAQ and NYSE exchanges. The biggest issue with Yahoo Finance is the recent change to the API in May. The data is good quality, includes both dividend/split adjusted and raw prices, but it's much more difficult to pull the data with packages like R quantmod than before.  Google is fine as well, but there are some missing data points and you can't unadjust the prices (or is it that they're all unadjusted and you can't get adjusted? I can't recall). I use Google at home, when I can't pull from Bloomberg directly and when I'm not too concerned with accuracy.  Quandl seems quite good but I haven't tried them. There's also a newer website called www.alphavantage.co, I haven't tried them yet either but their data seems to be pretty good quality from what I've heard. http://www.pacificrubiales.com/investor-relations/reports.html does have financial reports on their website for the example you list.  There is the potential for some data to not be easily imported into a format that Yahoo! Finance uses would be my guess for why some data may be missing though an alternative explanation for some companies would be that they may not have been around for a long enough time period to report this information,e.g. if the company is a spin-off of an existing company. "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." You bought 1 share of Google at $67.05 while it has a current trading price of $1204.11. Now, if you bought a widget for under $70 and it currently sells for over $1200 that is quite the increase, no? Be careful of what prices you enter into a portfolio tool as some people may be able to use options to have a strike price different than the current trading price by a sizable difference. Take the gain of $1122.06 on an initial cost of $82.05 for seeing where the 1367% is coming. User error on the portfolio will lead to misleading statistics I think as you meant to put in something else, right? Nanex just doesn't have the data. Some guy at CNBC, knowing that this stuff is great fodder for pageviews, *particularly* when there is a mysterious unnamed firm (its much too boring when there is an actual firm named, and the reason turns out to be something mundane like a slow market data feed), scooped it up and packaged it into a fear mongering story, and here we are. Sheegan has a great explanation of how the TBA market contributes to  mortgage rates. The 30 Year Mortgage rates are closely tied to the 10-Year Treasury.  One can track this rate at many stock quoting sites using symbol TNX. I will assume that you are not asking in the context of high frequency trading, as this is Personal Finance Stack Exchange. It is completely acceptable to trade odd lots for retail brokerage customers. The odd lot description that you provided in your link, from Interactive Brokers is correct. But even in that context, it says, regarding the acceptability of odd lots to stock exchanges: The exception is that odd lots can be routed to NYSE/ARCA/AMEX, but   only as part of a basket order or as a market-on-close (MOC) order. Google GOOG is traded on the NASDAQ. Everything on the NASDAQ is electronic, and always has been. You will have no problem selling or buying less than 100 shares of Google.  There is also an issue of higher commissions with odd lots: While trading commissions for odd lots may still be higher than for   standard lots on a percentage basis, the popularity of online trading   platforms and the consequent plunge in brokerage commissions means   that it is no longer as difficult or expensive for investors to   dispose of odd lots as it used to be in the past. Notice what it says about online trading making it easier, not more difficult, to trade odd lots. Traditionally, the Dow Jones Industrial Average (DJIA) was only comprised of stocks that were traded on the New York Stock exchange.  Neither Apple (AAPL) nor Google (GOOG) are traded on the New York Stock Exchange but instead are traded on NASDAQ.  All NASDAQ tickers are four characters long and all NYSE tickers are only three or less characters long (e.g. IBM or T (AT&T)). However in 1999, MSFT became the first NASDAQ stock to be included in the DJIA.  Given that AAPL now has the largest market capitalization of any company in U.S. history, I think it is likely if they retain that position, that they would eventually be let into the DOW club too, perhaps, ironically, even supplanting Microsoft. It's got to be a bad chunk of data on Google.  Yahoo finance does not show that anomaly for 1988, nor does the chart from Home Depot's investor relations site: For each class A share (GOOGL) there's a class C share (GOOG), hence the missing half in your calculation. The almost comes from the slightly higher market price of the class A shares (due to them having voting powers) over class C (which have no voting powers). There's also class B share which is owned by the founders (Larry, Sergei, Eric and perhaps some to Stanford University and others) and differs from class A by the voting power. These are not publicly traded. "I'm familiar with and have traded U.S.-listed LEAPS and I've always used the CBOE quotes page you linked to.  So, I too was surprised I couldn't find 3M (MMM) LEAPS quotes at that page, even after checking the ""List all options, LEAPS, Credit Options & Weeklys if avail."" radio button.  Used to work! Fortunately, I was able to get access to the full chain of option quotes from the CBOE's other quotes page:  Go to the ""Quotes & Data"" menu, then select Delayed Quotes - NEW!  Here's how: I think the new interface is terrible: it's too many steps to get to the information desired.  I preferred the all-in-one table of the Delayed Quotes Classic page, the one you linked to. As to why that classic page isn't yielding the full chain, I can only suggest it is a recently introduced bug (software defect).  I certainly was able to get LEAPS quotes from that page before. On Yahoo! Finance option quotes: I don't know why their chain is incomplete – I can't see the logic, for instance, as to why MMM Jan 2012 60 calls are missing.  I thought at first it may be lack of volume or open interest, but nope.  Anyway, I don't trust Yahoo! to provide accurate, reliable quotes anyway, having seen too many errors and missing data in particular in the feed of Canadian stocks, which I also trade. I rely on the exchange's quotes, and my broker's real-time quotes.  I check Yahoo! only for convenience sake, and when it actually matters I go to the other more reliable sources. For what it's worth, though, you can also get full chain option quotes at NASDAQ.  See here for the 3M (MMM) example then click on the ""Jan 12"" link near the top.  However, I would consider CBOE's quotes more definitive, since they are the options exchange."