Recommendation on Options Back Testing tool please
Power Options is one such example of what you seek, not cheap, but one good trade will recover a year's fee.  There's a lot you can do with the stock price alone as most options pricing will follow Black Scholes.  Keep in mind, this is a niche, these questions, while interesting to me, generate little response here. "As JoeTaxpayer says, there's a lot you can do with just the stock price. Exploring that a bit: Stock prices are a combination of market sentiment and company fundamentals. Options are just a layer on top of that. As such, options are mostly formulaic, which is why you have a hard time finding historical option data -- it's just not that ""interesting"", technically. ""Mostly"" because there are known issues with the assumptions the Black-Scholes formula makes. It's pretty good, and importantly, the market relies on it to determine fair option pricing. Option prices are determined by: Relationship of stock price to strike. Both distance and ""moneyness"". Time to expiration. Dividends. Since dividend payments reduce the intrinsic value of a company, the prospect of dividend payments during the life of a call option depresses the price of the option, as all else equal, without the payments, the stock would be more likely to end up in the money. Reverse the logic for puts. Volatility. Interest rates. But this effect is so tiny, it's safe to ignore. #4, Volatility, is the biggie. Everything else is known. That's why option trading is often considered ""volatility trading"". There are many ways to skin this cat, but the result is that by using quoted historical values for the stock price, and the dividend payments, and if you like, interest rates, you can very closely determine what the price of the option would have been. ""Very closely"" depending on your volatility assumption. You could calculate then-historical volatility for each time period, by figuring the average price swing (in either direction) for say the past year (year before the date in question, so you'd do this each day, walking forward). Read up on it, and try various volatility approaches, and see if your results are within a reasonable range. Re the Black-Scholes formula,  There's a free spreadsheet downloadable from http://optiontradingtips.com. You might find it useful to grab the concept for coding it up yourself. It's VBA, but you can certainly use that info to translate in your language of choice. Or, if you prefer to read Perl, CPAN has a good module, with full source, of course. I find this approach easier than reading a calculus formula, but I'm a better developer than math-geek :)" Based on my experience with OpenQuant, which is a development platform for automated trading strategies (and therefore can be easily be used for backtesting your personal strategy), I can give a little insight into what you might look for in such a platform.  OpenQuant is a coding environment, which reads data feeds from a variety of sources (more on that in the second point), and runs the code for your strategy on that data and gives you the results. The data could be imported from a live data feed or from historical data, either through numerous API's, CSV/Excel, etc. You can write your own strategies using the custom C# libraries included with the software, which spares you from implementing your own code for technical indicators, basic statistical functions, etc. Getting the data is another issue. You could use joe's strategy and calculate option prices yourself, although you need to exercise caution when doing this to test a strategy. However, there is no substitute for backtesting a strategy on real data. Markets change over time, and depending on how far back you're interested in testing your strategy, you may run into problems. The reason there is no substitute for using real data is that attempting to replicate the data may fail in some circumstances, and you need a method of verifying that the data you're generating is correct and realistic. Calculating a few values, comparing them to the real values, and calibrating accordingly is a good idea, but you have to decide for yourself how many checks you want to do. More is better, but it may not be enough to realistically test your strategy. Disclaimer: Lest you interpret my post as a shameless plug for the OpenQuant platform, I'll state that I found the interface awful (it looked vaguely like Office 2000 but ten years too late) and the documentation woefully incomplete. I last used the software in 2010, so it may have improved in the intervening years, but your mileage may vary. I only use it as an example to give some insight into what you might look for in a backtesting platform. When you actually begin trading, a different platform is likely in order.  That being said, it responded fairly quickly and the learning curve wasn't too steep. The platform wasn't too expensive at the time (about $700 for a license with no data feeds, I think) but I was happy that the cost wasn't coming out of my pocket. It's only gotten more expensive and I'm not sure it's worth it.
If you had a trading system, and by trading system I mean the criteria setup that you will take a trade on, then once a setup comes up at what price will you open the trade and at what price you will close the trade. As an example, if you want to buy once price breaks through resistance at $10.00 you might place your buy order at $10.05. So once you have a written trading system you could do backtesting on this system to get a percentage of win trades to loosing trades, your average win size to average lose size, then from this you could work out your expectancy for each trade that you follow your trading system on. I'm sorry for adding another answer @MatthewFlaschen but it is too long for a comment. It depends on the situation. Say you buy shares of the Apple Inc. and want to know what is the lost opportunity cost. You need to find out what other opportunities are. In other words what are the other possible types of investments you consider. For example in theory you could try to invest in any company from S&P 500, but is it really possible (I don’t mean investing directly in index) . Are you really capable of researching each company.  So in your case you would consider only a few companies as alternative solutions. Also after different time period each choice may be your lost opportunity cost.  To measure the risk you have to: In conclusion I want to say that my goal was to picture in general how the process looks. Also this is just an exemplary answer. All is about in what finance field you are interested. For example in one field you use Internal Rate of Return and in other Value at Risk. Opportunity cost is to vague to exactly tell how measure its risk of wrong anticipation. It connects in every finance field and in every field you have different ways do deal with it. If you specify your question more, maybe someone will provide a better answer. "Okay, I'm going to give you my opinion based on experience; not any technical understanding. The options - by themselves - are pretty meaningless in terms of determining their value. The business plan going forward, their growth expectations, the additional options to be authorized, the additional preferred stock offers they anticipate, even current estimated value of the company are some of the pieces of data you will be needing. I also want to say something cynical, like ""to hell with the stock options give me cold hard"" but that's just me. (My experience two-times so far has shown stock options to be worth very very little.)" I can't provide a list, but when I took out my Stocks and Shares, I extensively researched for a good, cheap, flexible option and I went with FoolShareDealing.  I've found them to be good, and their online trading system works well.  I hope that's still the case. I've looked into Thinkorswim; my father uses it. Although better than eTrade, it wasn't quite what I was looking for. Interactive Brokers is a name I had heard a long time ago but forgotten. Thank you for that, it seems to be just what I need. Oanda.com trades spot forex and something they call box options, it's not quite what you are looking for, but maybe worth looking up. You can use Google Finance Stock Screener for screening US stocks. Apparently it doesn't have the specific criterion (Last Price % diff from 52 week low) you are (were!) looking for.  I believe using its api you can get it, although it won't exactly be a very direct solution. You would have to compare your backtesting to what you will be doing in real trading, and try to have the backtesting as close to your real trading as possible. Note: you may never get the backtesting to match your real trading exactly but you need to get as close as possible. The whole purpose of backtesting is to check if your trading strategies - your signals, entries and exits, and your stops - are profitable over various market conditions. As you would be using actual closes to do your real trading you should be using this to also do your backtesting. Rather than using adjusted data to get an idea of your total return from your backtesting, you can always add the value of the dividends and other corporate actions to the results from using the actual data. You may even find a way to add any dividends and other corporate action to your results automatically, i.e. any dividend amount added to your total return if the stock is held during the ex-dividend date. If you are using adjusted data in your backtesting this may affect any stops you have placed, i.e. it may cause your stop to be triggered earlier or later than in real trading. So you will need to determine how you will treat your stops in real trading.  Will you adjust them when there is corporate action such as dividends?  Or will you leave them constant until actual prices have gone up? If you will be leaving your stops constant then you should definitely be using actual data in your backtesting to better match your real trading. "Unfortunately, there is very little data supporting fundamental analysis or technical analysis as appropriate tools to ""time"" the market. I will be so bold to say that technical analysis is meaningless. On the other hand, fundamental analysis has some merits. For example, the realization that CDOs were filled with toxic mortgages can be considered a product of fundamental analysis and hence provided traders with a directional assumption to buy CDSs. However, there is no way to tell when there is a good or bad time to buy or sell. The market behaves like a random 50/50 motion. There are many reasons for this and interestingly, there are many fundamentally sound companies that take large dips for no reason at all. Depending on your goal, you can either believe that this volatility will smooth over long periods and that the market has generally positive drift. On the other hand, I feel that the appropriate approach is to remain active. You will be able to mitigate the large downswings by simply staying small and diversifying  - not in the sense of traditional finance but rather looking for uncorrelated products. Remember, volatility brings higher levels of correlation. My second suggestion is to look towards products like options to provide a method of shaping your P/L - giving up upside by selling calls against a long equity position is a great example. Ground your trades with fundamental beliefs if need be, but use your tools and knowledge to combat risks that may create long periods of drawdown." If I were in your position, I'd start reading about the job on my spare time. There are lots of good books that are available free if you know where to look *cough pirated*  A couple of titles to start you off. (note I haven't personally gone through all of them)   Market Risk Analysis - Carol Alexander  Modeling Risk: Applying Monte Carlo Simulation, Real Options Analysis, Forecasting, and Optimization Techniques-  Johnathan   Derivatives: Markets, Valuation, and Risk Management - Robert E. Whaley   Best of luck. @bstpierre gave you an example of a portfolio similar to IFA's 70 portfolio. Please, look other variants of example portfolios there and investigate which would suit to you.  Although the example portfolios are not ETF-based, required by the op, you can rather easily check corresponding components with this tool here. Before deciding your portfolio, fire up a spreadsheet (samples here) and do calculations and do not underestimate things below: Bogleheads have already answered this type of questions so why not look there? Less reinventing the wheel: google retirement portfolios site:bogleheads.org. I am not making any recommendations like other replies because financial recommendations devalue. I hope I steered you to the right track, use less time to pick individual funds or stocks and use more time to do your research. "I'd start with a Google search for ""best backtesting tools."" Does your online brokerage offer anything? You already understand that the data is the important part.  The good stuff isn't free. But yeah, if you have some money to spend you can get more than enough data to completely overwhelm you. :)" I also searched for some time before discovering Market Archive, which AFAIK is the most affordable option that basically gives you a massive multi-GB dump of data.  I needed sufficient data to build a model and didn't want to work through an API or have to hand-pick the securities to train from.  After trying to do this on my own by scraping Yahoo and using the various known tools, I decided my time was better spent not dealing with rate-limiting issues and parsing quirks and whatnot, so I just subscribed to Market Archive (they update the data daily). I've used Wikinvest before and think that's close to what you're looking for - but in Wiki-style rather than forums.  Otherwise, I agree with CrimsonX that The Motley Fool is a good place to check out. Right, that's my understanding of the problem too. I tried some of the indices last night (not necessarily the ones you are suggesting), but when pulling them into COMP it only provided the price return, not the total return including coupons. This latter part is still the challenge.