How quickly does short float ratio/percent change?
The short float ratio and percent change are all calculated based on the short interest (the total number of shares shorted).  The short interest data for Nasdaq and NYSE stocks is published every two weeks. NasdaqTrader.com shows the exact dates for when short interest is published for Nasdaq stocks, and also says the following: FINRA member firms are required to report their short positions as of settlement on (1) the 15th of each month, or the preceding business day if the 15th is not a business day, and (2) as of settlement on the last business day of the month.* The reports must be filed by the second business day after the reporting settlement date. FINRA compiles the short interest data and provides it for publication on the 8th business day after the reporting settlement date. The NYSE also shows the exact dates for when short interest is published for NYSE stocks, and those dates are exactly the same as for Nasdaq stocks. Since the short interest is only updated once every 2 weeks, there is no way to see real-time updating of the short float and percent change.  That information only gets updated once every 2 weeks - after each publication of the short interest.
The volatility measures how fast the stock moves, not how much. So you need to know the period during which that change occurred. Then the volatility naturally is higher the faster is the change. The value of the asset doesn't change just because of the exchange rate change. If a thing (valued in USD) costs USD $1 and USD $1 = CAN $1 (so the thing is also valued CAN $1) today and tomorrow CAN $1 worth USD $0.5 - the thing will continue being worth USD $1. If the thing is valued in CAN $, after the exchange rate change, the thing will be worth USD $2, but will still be valued CAN $1. What you're talking about is price quotes, not value. Price quotes will very quickly reach the value, since any deviation will be used by the traders to make profits on arbitrage. And algo-traders will make it happen much quicker than you can even notice the arbitrage existence. The optimal time period is unambiguously zero seconds.  Put it all in immediately.  Dollar cost averaging reduces the risk that you will be buying at a bad time (no one knows whether now is a bad or great time), but brings with it reduction in expected return because you will be keeping a lot of money in cash for a long time.  You are reducing your risk and your expected return by dollar cost averaging. It's not crazy to trade expected returns for lower risk.  People do it all the time.  However, if you have a pot of money you intend to invest and you do so over a period of time, then you are changing your risk profile over time in a way that doesn't correspond to changes in your risk preferences.  This is contrary to finance theory and is not optimal.  The optimal percentage of your wealth invested in risky assets is proportional to your tolerance for risk and should not change over time unless that tolerance changes. Dollar cost averaging makes sense if you are setting aside some of your income each month to invest.  In that case it is simply a way of being invested for as long as possible.  Having a pile of money sitting around while you invest it little by little over time is a misuse of dollar-cost averaging. Bottom line: forcing dollar cost averaging on a pile of money you intend to invest is not based in sound finance theory.  If you want to invest all that money, do so now.  If you are too risk averse to put it all in, then decide how much you will invest, invest that much now, and keep the rest in a savings account indefinitely.  Don't change your investment allocation proportion unless your risk aversion changes. There are many people on the internet and elsewhere who preach the gospel of dollar cost averaging, but their belief in it is not based on sound principles.  It's just a dogma. The language of your question implies that you may be interested in sound principles, so I have given you the real answer. "The charts on nasdaq.com are log based, if you look closely you can see that the spacing between evenly incremented prices is tighter at the top of the chart and wider at the bottom.   It's easiest to see on a stock with a wide price range using candlestick where you can clearly see the grid.  I'm also not seeing the ""absurdism"" you indicate when I look at google finance with the settings ticked to use log on the price axis.  I see what I'd expect which is basically a given vertical differential on the price axis representing the same percentage change in price no matter where it is located. For example if I look at GOOG from the earliest date they have (Aug 20 2004) to a nice high point (dec 7 2007) I see a cart where the gap from the the bottom of the chart (seems to be right around 100) to the 200 point, (a 100% increase) is the same as from 200 to 400 (a 100% increase) is the same as 400 to 800 (a 100# increase)   That's exactly what I expect from a 'log' chart on a financial site, each relative move up or down of the same distance, represents the same relative change in value. So I'm having difficulty understanding what your complaint is. (note: I'm using chrome, which is the browser I'd expect to work best with any google website.  results with other browsers could of course vary)  If you want to do some other wacky math with the axis then I humbly suggest that something like Excel is your friend.   Goto the charts at nasdaq.com  get the chart displaying the period you care about, click the chart to display the unlying data, there will be an option to download the data.  cram it into excel and go wild as you want with charting it out.  e.g. note that step 2 links to client side javascript, so you will need javascript enabled, if you are running something like noscript, disable it for this site.  Also since the data opens in a new window, you may also need to enabled 'popups' for the site. (and yes, I sometimes get an annoying news alert advert popup  and have to close it when the chart first appears.. oh well it pays the rent and nasdaq is not charging you so for access so such is the price for a free site. )" This is a gross simplification as there are a few different ways to do this. The principle overall is the same though. To short a stock, you borrow X shares from a third party and sell them at the current price. You now owe the lender X shares but have the proceeds from the sale. If the share price falls you can buy back those shares at the new lower price, return them to the lender and pocket the difference. The risk comes when the share price goes the other way, you now owe the lender the new value of the shares, so have to find some way to cover the difference. This happened a while back when Porsche made a fortune buying shares in Volkswagen from short sellers, and the price unexpectedly rose. The shortest-hand yet most reliable metric is daily volume / total shares outstanding.  A security with a high turnover rate will be more efficient than a lower one, ceteris paribus. The practical impacts are tighter spread and lower average percentage change between trades.  A security with a spread of 0% and an average change of 0% between trades is perfectly efficient. "Yes, there are non-stock analogs to the Price/Earnings ratio. Rental properties have a Price/Rent ratio, which is analogous to stocks' Price/Revenue ratio.  With rental properties, the ""Cap Rate"" is analogous to the inverse of the Price/Earnings ratio of a company that has no long-term debt. Bonds have an interest rate.  Depending on whether you care about current dividends or potential income, the interest rate is analogous to either a stock's dividend rate or the inverse of the Price/Earnings ratio." "Here's the slippage I was talking about - - - this is when I was trading DXO or around that time.  the ultra shares----interesting read at least.  ""Based on data from October 22, 2008 to January 26, 2009, the S&amp;P 500 had a daily standard deviation of 3.62%.  If you were to invest in SDS, an UltraShort ETF which has the S&amp;P 500 as its underlying index, and were to hold it for a year, you should expect to lose between 34% and 74% of your money, if the S&amp;P 500 is flat for that period.  This assumes that there are no transaction costs, and that the expense ratio is 0% (in fact, it's 0.91%.)  My experiment also assumed that daily stock market returns follow a normal distribution.  In fact, the the distribution of daily stock market returns is leptokurtotic (it has fat tails.)  According to my mathematical intuition (the Ph.D. is in math, in case you were curious,) if I had performed the experiment with a leptokurtotic distribution, the losses would have been larger.  Obviously, this could be checked, but the results are bad enough as it is.""   http://www.altenergystocks.com/archives/2009/02/ultrapromises_fall_short.html" PE ratio is the current share price divided by the prior 4 quarters earnings per share. Any stock quote site will report it. You can also compute it yourself. All you need is an income statement and a current stock quote. "How accurate is Implied Volatility in predicting future moves? How would you measure this?  If the implied volatility says that there's a 1% chance that a stock will double, and it doubles, was it ""right""?  You could also say that it says there's a 99% change that it doesn't double, so was it ""wrong""?   What you could measure is the variance of daily returns over a time period, and see how well that compares to implied volatility, but there's no way to compare IV with the absolute price movement.  If a stock goes up 0.01 each day, then the variance is 0 (the daily returns are the same each day), but over 250 the stock would go up $2.50." "This is called ""change"" or ""movement"" - the change (in points or percentage) from the last closing value. You can read more about the ticker tape on Investopedia, the format you're referring to comes from there." &gt; A short position also loses money if the stock just appreciates more slowly than the broader market, which is one way an overvaluation can correct itself.  Is there a derivative based on the literal second derivative (acceleration) of the stock price? If so, you'd be able to short those, yes? "Thanks!  Do you know how to calculate the coefficients from this part?:  ""The difference between the one-year rate and the spread coefficients represents the response to a change in the one-year rate. As a result, the coefficient on the one-year rate and the difference in the coefficients on the one-year rate and spread should be positive if community banks, on average, are asset sensitive and negative if they are liability sensitive. The coefficient on the spread should be positive because an increase in long-term rates should increase net interest income for both asset-sensitive and liability-sensitive banks.""  The one-year treasury yield is 1.38% and the ten-year rate is 2.30%.  I would greatly appreciate it if you have the time!" This is a really easy problem. If you're genuinely having trouble, maybe don't be a finance major? All you need to do is know the formulas for the ratios and plug in the variables. Simple and clean.  However, if you're lazy and trying to get free answers off of reddit, then you could have saved the time you took to post this question and actually do the problem. You probably would have gotten the answer all by yourself without much help. Don´t forget that changing volatility will have an impact on the time value too! So at times it can happen that your time value is increasing instead of decreasing, if the underlying (market) volatility moves up strongly. Look for articles on option greeks, and how they are interdependent. Some are well explaining in simple language.