Calculating the value of an investors inventory
Is it just -34*4.58= -$155.72 for CCC and -11*0.41= -$4.51 for DDD? Yes it needs to be recorded as negative because at some point in time, the investor will have to spend money to buy these shares [cover the short sell and return the borrowed shares]. Whether the investor made profit or loss will not be reflected as you are only reflecting the current share inventory.
"From Wikipedia: Usage Because EV is a capital structure-neutral metric, it is useful when   comparing companies with diverse capital structures. Price/earnings   ratios, for example, will be significantly more volatile in companies   that are highly leveraged. Stock market investors use EV/EBITDA to compare returns between   equivalent companies on a risk-adjusted basis. They can then   superimpose their own choice of debt levels. In practice, equity   investors may have difficulty accurately assessing EV if they do not   have access to the market quotations of the company debt. It is not   sufficient to substitute the book value of the debt because a) the   market interest rates may have changed, and b) the market's perception   of the risk of the loan may have changed since the debt was issued.   Remember, the point of EV is to neutralize the different risks, and   costs of different capital structures. Buyers of controlling interests in a business use EV to compare   returns between businesses, as above. They also use the EV valuation   (or a debt free cash free valuation) to determine how much to pay for   the whole entity (not just the equity). They may want to change the   capital structure once in control. Technical considerations Data availability Unlike market capitalization, where both the market price and the   outstanding number of shares in issue are readily available and easy   to find, it is virtually impossible to calculate an EV without making   a number of adjustments to published data, including often subjective   estimations of value: In practice, EV calculations rely on reasonable estimates of the   market value of these components. For example, in many professional   valuations: Avoiding temporal mismatches When using valuation multiples such as EV/EBITDA and EV/EBIT, the   numerator should correspond to the denominator. The EV should,   therefore, correspond to the market value of the assets that were used   to generate the profits in question, excluding assets acquired (and   including assets disposed) during a different financial reporting   period. This requires restating EV for any mergers and acquisitions   (whether paid in cash or equity), significant capital investments or   significant changes in working capital occurring after or during the   reporting period being examined. Ideally, multiples should be   calculated using the market value of the weighted average capital   employed of the company during the comparable financial period. When calculating multiples over different time periods (e.g. historic   multiples vs forward multiples), EV should be adjusted to reflect the   weighted average invested capital of the company in each period. In your question, you stated: The Market Cap is driven by the share price and the share price is   determined by buyers and sellers who have access to data on cash and   debts and factor that into their decision to buy or sell. Note the first point under ""Technical Considerations"" there and you will see that the ""access to data on cash and debts"" isn't quite accurate here so that is worth noting. As for alternatives, there are many other price ratios one could use such as price/earnings, price/book value, price/sales and others depending on how one wants to model the company. The better question is what kind of investing strategy is one wanting to use where there are probably hundreds of strategies at least. Let's take Apple as an example. Back on April 23, 2014 they announced earnings through March 29, 2014 which is nearly a month old when it was announced. Now a month later, one would have to estimate what changes would be made to things there. Thus, getting accurate real-time values isn't realistic. Discounted Cash Flow is another approach one can take of valuing a company in terms of its future earnings computed back to a present day lump sum." "It's not necessarily bad but it can cause the stock price to become a lot more volatile. Depends on which side of the bet you're on ;) Suppose a hedge fund manager thinks a company is poorly run. He may buy a ton of shares so that he can get rid of the current CEO and replace it with his/her own. For the hedge fund and others long on the stock, this is good. Those who are trading options or using some short-term strategies could get screwed because of the sudden volatility.  My next point is related to the above. What is the intrinsic value of a stock? The current price of a stock is the equilibrium of all investor's perception of the stock's value. Professionals make up a value for a stock using models such as DCF. Once they do so they trade based on what they believe the value of the stock is. You might calculate a stock is worth 70 and I believe it's 80 so the stock price is going to fluctuate a bit but it should keep within that range (assuming we're the only investors). Then comes a hedge fund manager, say Carl Icahn, and discloses a stake in our stock. ""Wow, the stock must be really valuable!"" Everyone starts buying this stock so up it goes to 90, simply because the guy who seems to know what he's doing bought it. The point here is that now it's not trading based on intrinsic value, now it's purely psychological. Ie. it's now a momentum stock, which you have no idea when it'll crash. Look at Tesla, Netflix, or just google momentum stocks. All the big crashes in stock prices happen when these big funds unload their stocks. A surge in supply will cut the price. The problem is you can't predict when some fund manager will decide to sell some stake of his.  Tying everything together is liquidity. The more liquid a stock is, the easier it is to obtain and the less volatile it is. The more people playing the game, with not too big shares of stock, the faster the price will converge to some equilibrium and with less volatility. Institutional investors take away liquidity." "I used to be in research department for big financial data company.   Tell your son that there are three factors: Most people think that net sales vs. expectations is the only factor.  It might not even be the biggest.  It is simply how much money did company make.  Note that this is not how many units they sold.  For most companies they will have adjustable pricing and incentives in their sector.  For example let's talk about a new company selling Superman Kid's Bikes (with a cape the flips out when you hit a certain speed).  The company has it in Walmart at one price, Target at another, Toys R' Us even cheaper, Amazon (making more profit there), and other stores.  They are doing ""OK"" come Dec. 1 but holiday season being half way over they slash price from $100 to $80 because they have tons of inventory.  What are looking at her is how much money did they make.  Note that marketing, advertising, legal (setting up contracts) are a bit fixed. In my opinion consumer sentiment is the #1 thing for a company that sells a product.  Incredible consumer sentiment is like millions of dollars in free advertising.  So let's say Dec. 15th comes and the reviews on the Superman Bike are through the roof.  Every loves it, no major defects.  Company can't even supply the retailers now because after slashing the price it became a great buy.  A common investor might be pissed that some dummy at the company slashed the prices so they could have had a much better profit margin, but at the same time it wouldn't have led to an onslaught of sales and consumer sentiment. And the last area is product sell-off.  This doesn't apply to all product but most.  Some products will only have a technology shelf life, some will actually go bad or out of fashion, and even selling Superman bikes you want to get those to the store because the product is so big.  So ignoring making a profit can a company sell off inventory at or around cost.  If they can't, even if they made a profit, their risk factor goes up. So let's get back to Superman Bikes.  This is the only product company ABC has.  They had expected holiday sales at 100 million and profits at 40 million.  They ended up at 120 million and 44 million.   Let's say their stock was $20 before any information was gathered by the public (remember for most companies info is gathered daily now so this is rather simplistic).  So you might expect that the stock would rise to maybe $24 - to which if you were an investor is a great profit. However this company has a cult consumer following who are waiting for the Captain America Bike (shoots discs) and the Hulk Bike (turns green when you go fast).  Let's say consumer sentiment and projections base off that put next holiday sales at $250 million.  So maybe the company is worth $40 a share now.  But consumer sentiment is funny because not only does it effect future projections but it also effects perceived present value of company - which may have the stock trading at $60 a share (think earnings and companies like Google).  Having a company people feel proud owning or thinking is cool is also a indicator or share worth. I gave you a really good example of a very successful company selling Superman Bikes... There are just as many companies that have the opposite happening.  Imagine missing sales goals by a few million with bad consumer feedback and all of a sudden your company goes from $20 to $5 a share." The total number of shares on April 1st is 100 + 180 + 275 = 555.  The price on April 1st is required.  The current price is stated as $2, but $2 * 555 = $1110 and the current fund values is stated as $1500.  Opting to take the current value as $1500, the price on April 1st can be calculated as $1500/555 = $2.7027. The amounts invested as number of shares x share price are: (Note these investment amounts do not match the example scenario's investment amounts, presumably because the example numbers are just made up.) The monthly returns can be calculated: The current values for each investor as invested amount x returns are: Checking the total: "Your company actually will most likely use some sort of options pricing model, either a binomial tree or black-scholes to determine the value for their accounting and, subsequently, for their issuance and realization.  First, market value of equity will be determined. Given you're private (although ""pre-IPO could mean public tomorrow,""), this will likely revolve around a DCF and/or market approaches.  Equity value will then be compared to a cap table to create an equity waterfall, where the different classes of stock and the different options will be valued along tranches. Keep in mind there might be liquidation preferences that would make options essentially further out of the money.  As such, your formulae above do not quite work. However, as an employee, it might be difficult to determine the necessary inputs to determine value.  To estimate it, however, look for three key pieces of information:  1. Current equity value  2. Option strike price  3. Maturity for Options  If the strike is close to the current equity value, and the maturity is long enough, and you expect the company to grow, then it would look like the options have more value than not.   Equity value can be derived from enterprise value, or by directly determining it via a DCF or guideline multiples.   Reliable forecasts should come from looking at the industry, listening to what management is saying, and then your own information as an insider." Yes, assuming that your cash flow is constantly of size 5 and initial investment is 100, the following applies: IRR of 5% over 3 years: Value of CashFlows: 4.7619 + 4.5351 + 4.3192 = 13.6162 NPV: 100 - 13.6162 = 86.3838 Continuous compounding: 86.3838 * (1.05^3) = 100 In order to calculate the ratio you are looking for, just divide total debt by the market capitalization of the stock. Both values can be found on the link you provided. The market capitalization is the market value of equity. "My answer is Microsoft Excel.  Google ""VBA for dummies"" (seriously) and find out if your brokerage offers an 'API'.  With a brief understanding of coding you can get a spreadsheet that is live connected to your brokers data stream.  Say you have a spreadsheet with the 1990 value of each in the first two columns (cells a1 and b1).  Maybe this formula could be the third column, it'll tell you how much to buy or sell to rebalance them.   then to iterate the rebalance, set both a2 and b2 to =C1 and drag the formula through row 25, one row for each year.  It'll probably be a little more work than that, but you get the idea."