What drives the value of a stock? [duplicate]
For XOM if you were lucky enough to purchase on 20 Jan 16, at 73.18/share and sold on 15 July at 94.95 you would achieve a 29% return in six months.  Awesome.  You'd also get a dividend payment or two adding another percentage point per to your returns.   The one year chart for FB shows it increasing from ~95/share to ~129.  Yet no dividend was paid.  However, the 35.7% YTD for 2016 should make anyone happy. Both of these require excellent timing, and those kind of returns are unsustainable over the long haul.  Many people simply hold stocks.  Having the dividend is a nice bonus to some growth.   Why to people buy stocks?  For profit.  Sometimes dividend payers offer the best option, sometimes not.
It really is a stupid term.  What comes to mind with the term underwater?  drowning, sunk boats, cars and other property and flooding. All really stressful and damaging.   Underwater in mortgages, means you owe more than your house is worth, .... ER your home's value dropped below the value of your mortgage.  It does suck but  it doesnt mean they are behind on their mortgage and doesnt suck as much as people who are behind.  it isnt really something to worry about except for the future when you resell. For a lot of people it is just something they can ignore.   In theory, they should get a lower tax bill.   Underwater just seems like an odd term for something like your home value dropping below the price your paid for it. If you buy a new car, you can pretty much claim to be underwater as you drive it off the lot, because your car simply isnt worth what you paid for it the second it becomes used.  not saying it isnt an interesting stat, or that it is of no concern, it's just an odd term.  To me it is more fitting for people behind in their payments than for people whose property lost value.  (and yeah i get it is more dire for investors and somewhat for landlords but not always) "Vitalik has mentioned this in a comment but I think it ought to be expanded upon: Companies that aren't already penny stocks really don't stand to gain anything from trying to prevent short interest.  Short selling does not inherently lower the stock price - not any more so than any other kind of selling.  When somebody shorts a stock, it's simply borrowed from another investor's margin; as long as it's not a naked short resulting in an FTD (Failure To Deliver) then it does not add any ""artificial"" selling pressure. In fact, shorting can actually drive the price up in the long term due to stops and margin calls.  Not a guarantee, of course, but if a rally occurs then a high short interest can cause a cascade effect from the short ""squeeze"", resulting in an even bigger rally than what would have occurred with zero short interest.  Many investors actually treat a high short interest as a bullish signal. Compare with margin buying - essentially the opposite of short selling - which has the opposite effect.  If investors buy stocks on margin, then if the value of that stock decreases too rapidly they will be forced to sell, which can cause the exact same cascade effect as a short interest but in the opposite direction.  Shorting is (in a sense) evening out the odds by inflating the buying pressure at lower stock prices when the borrowers decide to cover and take profits. Bottom line is that, aside from (illegal) insider trading, it doesn't do businesses any good to try to manipulate their stock price or any trading activity.  Yes, a company can raise capital by selling additional common shares, but a split really has no effect on the amount of capital they'd be able to raise because it doesn't change the actual market cap, and a dilution is a dilution regardless of the current stock price.  If a company's market cap is $1 billion then it doesn't matter if they issue 1 million shares at $50.00 each or 10 million shares at $5.00 each; either way it nets them $50 million from the sale and causes a 5% dilution, to which the market will react accordingly. They don't do it because there'd be no point." The folks who hold stock are the legal owners of the company. If a majority of stock holders become unhappy with the management of a company they can fire the executives and put in new management, or they can direct the company to close its doors and sell off its assets. As a crude approximation, the stock holders are happier when the stock price goes up and unhappier when it goes down. Therefore, executives are highly motivated to drive the stock price up.  A frequent criticism of corporate governence is that management can be so motivated to drive the stock price up, that they will take actions that drive the stock price up in the current year, even if undercuts the company in the long term. "Some thoughts on your questions in order, Duration: You might want to look at the longest-dated option (often a ""LEAP""), for a couple reasons. One is that transaction costs (spread plus commission, especially spread) are killer on options, so a longer option means fewer transactions, since you don't have to keep rolling the option. Two is that any fundamentals-based views on stocks might tend to require 3-5 years to (relatively) reliably work out, so if you're a fundamental investor, a 3-6 month option isn't great. Over 3-6 months, momentum, short-term news, short squeezes, etc. can often dominate fundamentals in determining the price. One exception is if you just want to hedge a short-term event, such as a pending announcement on drug approval or something, and then you would buy the shortest option that still expires after the event; but options are usually super-expensive when they span an event like this. Strike: Strike price on a long option can be thought of as a tradeoff between the max loss and minimizing ""insurance costs."" That is, if you buy a deeply in-the-money put or call, the time value will be minimal and thus you aren't paying so much for ""insurance,"" but you may have 1/3 or 1/2 of the value of the underlying tied up in the option and subject to loss. If you buy a put or call ""at the money,"" then you might have only say 10% of the value of the underlying tied up in the option and subject to loss, but almost the whole 10% may be time value (insurance cost), so you are losing 10% if the underlying stock price stays flat. I think of the deep in-the-money options as similar to buying stocks on margin (but the ""implied"" interest costs may be less than consumer margin borrowing rates, and for long options you can't get a margin call). The at-the-money options are more like buying insurance, and it's expensive. The commissions and spreads add significant cost, on top of the natural time value cost of the option. The annual costs would generally exceed the long-run average return on a diversified stock fund, which is daunting. Undervalued/overvalued options, pt. 1: First thing is to be sure the options prices on a given underlying make sense at all; there are things that ""should"" hold, for example a synthetic long or short should match up to an actual long or short. These kinds of rules can break, for example on LinkedIn (LNKD) after its IPO, when shorting was not permitted, the synthetic long was quite a bit cheaper than a real long. Usually though this happens because the arbitrage is not practical. For example on LNKD, the shares to short weren't really available, so people doing synthetic shorts with options were driving up the price of the synthetic short and down the price of the synthetic long. If you did actually want to be long the stock, then the synthetic long was a great deal. However, a riskless arbitrage (buy synthetic long, short the stock) was not possible, and that's why the prices were messed up. Another basic relationship that should hold is put-call parity: http://en.wikipedia.org/wiki/Put%E2%80%93call_parity Undervalued/overvalued options, pt. 2: Assuming the relationship to the underlying is sane (synthetic positions equivalent to actual positions) then the valuation of the option could focus on volatility. That is, the time value of the option implies the stock will move a certain amount. If the time value is high and you think the stock won't move much, you might short the option, while if the time value is low and you think the stock will move a lot, you might buy the option. You can get implied volatility from your broker perhaps, or Morningstar.com for example has a bunch of data on option prices and the implied components of the price model. I don't know how useful this really is though. The spreads on options are so wide that making money on predicting volatility better than the market is pretty darn hard. That is, the spread probably exceeds the amount of the mispricing. The price of the underlying is more important to the value of an option than the assumed volatility. How many contracts: Each contract is 100 shares, so you just match that up. If you want to hedge 100 shares, buy one contract. To get the notional value of the underlying multiply by 100. So say you buy a call for $30, and the stock is trading at $100, then you have a call on 100 shares which are currently priced at $10,000 and the option will cost $30*100=3,000. You are leveraged about 3 to 1. (This points to an issue with options for individual investors, which is that one contract is a pretty large notional value relative to most portfolios.)" "What you are seeking is termed ""Alpha"", the mispricing in the market. Specifically, Alpha is the price error when compared to the market return and beta of the stock. Modern portfolio theory suggests that a portfolio with good Alpha will maximize profits for a given risk tolerance. The efficient market hypotheses suggests that Alpha is always zero. The EMH also suggests that taxes, human effort and information propagation delays don't exist (i.e. it is wrong). For someone who is right, the best specific answer to your question is presented Ben Graham's book ""The Intelligent Investor"" (starting on page 280). And even still, that book is better summarized by Warren Buffet (see Berkshire Hathaway Letters to Shareholders). In a great disservice to the geniuses above it can be summarized much further: closely follow the company to estimate its true earnings potential... and ignore the prices the market is quoting. ADDENDUM: And when you have earnings potential, calculate value with: NPV = sum(each income piece/(1+cost of capital)^time) Update: See http://finance.fortune.cnn.com/2014/02/24/warren-buffett-berkshire-letter/ ""When Charlie Munger and I buy stocks..."" for these same ideas right from the horse's mouth" A company's stock value is indicative of the market's collective belief of the future of the company. The relationship of between price and book value will vary according to the quality of the company, the category of stock, etc. In extreme cases, say Bank of America, the stock trades at a fraction of book, because BOA's books are a fantasy by most people's reckoning. There are two ways that an asset can generate value.  One is that the asset generates some revenue (e.g. you buy a house for $100,000 and rent it out for $1,000 per month) and the second way is that the asset appreciates (e.g you buy a house for $100,000, you don't rent it out and 5 years later you sell it for $200,000).  Stocks are the same. You say: Every time it seems the share price dips. Does it?  Have you collected the data?   It may just be that you are remembering the events that seem most painful at the time. To move the market with your trade you need to be dealing in a large amount of shares.    Unless the stock is illiquid (e.g most VCT in the UK), I don’t think you are dealing in that large a number; if you were then you would likely have access to a real time feed of the order book and could see what was going on.