At what point do index funds become unreliable?
"A great deal of analysis on this question relies on misunderstandings of the market or noticing trends that happened at the same time but were not caused by each other.  Without knowing your view, I'll just give the basic idea. The amount of active management is self-correcting.  The reason people have moved out of actively managed funds is that the funds have not been performing well.  Their objective is to beat their benchmarks by profiting as they correct mispricing.  They are performing poorly because there is too much money chasing too few mispricings.  That is why the actively managed industry is shrinking.  If it gets small enough, presumably those opportunities will become more abundant and mispricing correction will become more profitable.  Then money will flow back into active funds. Relevant active management may not be what a lay person is thinking of.  At the retail level, we are observing a shift to passive funds, but there is still plenty of money in other places.  For example, pension and endowment funds normally have an objective of beating a market benchmark like the Russell 3000.  As a result they are constantly trying to find opportunities to invest in active management that really can outperform.  They represent a great deal of money and are nothing like the ""buy and forget"" stereotype we sometimes imagine.  Moreover, hedge funds and propreitary trading shops explicitly and solely try to correct mispricings.  They represent a very, very large bucket of money that is not shrinking.  Active retail mutual funds and individual investors are not as relevant for pricing as we might think.  More trading volume is not necessarily a good thing, nor is it the measure of market quality.  One argument against passive funds is that passive funds don't trade much.  Yet the volume of trading in the markets has risen dramatically over time as a result of technological improvements (algorithmic traders, mostly).  They have out-competed certain market makers who used to make money on inefficiencies of the market.  Is this a good thing or a bad thing?  Well, prices are more efficient now and it appears that these computers are more responsive to price-relevant information than people used to be.  So even if trading volume does decrease, I see no reason to worry that prices will become less efficient.  That's not the direction things have gone, even as passive investing has boomed. Overall, worries about passive investing rely on an assumption that there is not enough interest in and resources for making arbitrage profits to keep prices efficient.  This is highly counterfactual and always will be.  As long as people and institutions want money and have access to the markets, there will be plenty of resources allocated to price correction." "The argument you are making here is similar to the problem I have with the stronger forms of the efficient market hypothesis.  That is if the market already has incorporated all of the information about the correct prices, then there's no reason to question any prices and then the prices never change.  However, the mechanism through which the market incorporates this information is via the actors buying an selling based on what they see as the market being incorrect. The most basic concept of this problem (I think) starts with the idea that every investor is passive and they simply buy the market as one basket.  So every paycheck, the index fund buys some more stock in the market in a completely static way.  This means the demand for each stock is the same.  No one is paying attention to the actual companies' performance so a poor performer's stock price never moves.  The same for the high performer.  The only thing moving prices is demand but that's always up at a more or less constant rate. This is a topic that has a lot of discussion lately in financial circles.  Here are two articles about this topic but I'm not convinced the author is completely serious hence the ""worst-case scenario"" title. These are interesting reads but again, take this with a grain of salt.  You should follow the links in the articles because they give a more nuanced understanding of each potential issue.  One thing that's important is that the reality is nothing like what I outline above. One of the links in these articles that is interesting is the one that talks about how we now have more indexes than stocks on the US markets.  The writer points to this as a problem in the first article, but think for a moment why that is.  There are many different types of strategies that active managers follow in how they determine what goes in a fund based on different stock metrics.  If a stocks P/E ratio drops below a critical level, for example, a number of indexes are going to sell it.  Some might buy it.  It's up to the investors (you and me) to pick which of these strategies we believe in. Another thing to consider is that active managers are losing their clients to the passive funds.  They have a vested interest in attacking passive management." "As more actively managed funds are driven out of the market, the pricing of individual stocks should become less rational. I.e. more stocks will become underpriced relative to their peers. As stock prices become less rational, the reward for active investing will increase, since it will become easier to ""pick a winner"". Eventually, the market will reach a new equilibrium where only active investors who are good enough to turn a profit will remain. Even then, passive investment will still do roughly as well as ""the market"" since it has low overhead and minimal investment lag. There is no reason to expect the system to collapse, since it is characterized primarily by negative feedback loops rather than positive feedback.  The last few decades have seen a shift from active to passive investment because increased market transparency and efficiency have reduced the labor required to keep pricing rational. Basically, as people have gotten better at predicting stock performance, less active investment has been required to keep prices rational." "private investors that don't have the time or expertise for active investment.  This may be known as every private investor. An index fund ensures average returns. The bulk of active trading is done by private institutions with bucketloads of experts studying the markets and AI scraping every bit of data it can get (from the news, stock market, the weather reports, etc...). Because of that, to get above average returns an average percent of the time, singular private investors have to drastically beat the average large team of individuals/software. Now that index ETF are becoming so fashionable, could there be a tipping point at which the market signals that active investors send become so diluted that this ""index ETF parasitism"" collapses? How would this look like and would it affect only those who invest in index ETF or would it affect the stock market more generally? To make this question perhaps more on-topic: Is the fact (or presumption) that index ETF rely indirectly on active investment decisions by other market participants, as explained above, a known source of concern for personal investment? This is a well-covered topic. Some people think this will be an issue.   Others point out that it is a hard issue to bootstrap. I gravitate to this view. A small active market can support a large number of passive investors. If the number of active investors ever got too low, the gains & likelihood of gains that could be made from being an active investor would rise and generate more active investors. Private investing makes sense in a few cases. One example is ethics. Some people may not want to be invested, even indirectly, in certain companies." Private investors as mutual funds are a minority of the market.  Institutional investors make up a substantial portion of the long term holdings.  These include pension funds, insurance companies, and even corporations managing their money, as well as individuals rich enough to actively manage their own investments.   From Business Insider, with some aggregation:   Numbers don't add to 100% because of rounding.  Also, I pulled insurance out of household because it's not household managed.  Another source is the Tax Policy Center, which shows that about 50% of corporate stock is owned by individuals (25%) and individually managed retirement accounts (25%).   Another issue is that household can be a bit confusing.  While some of these may be people choosing stocks and investing their money, this also includes Employee Stock Ownership Plans (ESOP) and company founders.  For example, Jeff Bezos owns about 17% of Amazon.com according to Wikipedia.  That would show up under household even though that is not an investment account.  Jeff Bezos is not going to sell his company and buy equity in an index fund.   Anyway, the most generous description puts individuals as controlling about half of all stocks.  Even if they switched all of that to index funds, the other half of stocks are still owned by others.  In particular, about 26% is owned by institutional investors that actively manage their portfolios.   In addition, day traders buy and sell stocks on a daily basis, not appearing in these numbers.  Both active institutional investors and day traders would hop on misvalued stocks, either shorting the overvalued or buying the undervalued.   It doesn't take that much of the market to control prices, so long as it is the active trading market.  The passive market doesn't make frequent trades.  They usually only need to buy or sell as money is invested or withdrawn.  So while they dominate the ownership stake numbers, they are much lower on the trading volume numbers.   TL;DR:  there is more than enough active investment by organizations or individuals who would not switch to index funds to offset those that do.  Unless that changes, this is not a big issue.
"To add on to the other answers, in asking why funds have different price points one might be asking why stocks aren't normalized so a unit price of $196 in one stock can be directly compared to the same price in another stock.  While this might not make sense with AAPL vs. GOOG (it would be like comparing apples to oranges, pun intended, not to mention how would two different companies ever come to such an agreement) it does seem like it would make more sense when tracking an index.  And in fact less agreement between different funds would be required as some ""natural"" price points exist such as dividing by 100 (like some S&P funds do). However, there are a couple of reasons why two different funds might price their shares of the same underlying index differently. Demand - If there are a lot of people wanting the issue, more shares might be issued at a lower price.  Or, there might be a lot of demand centered on a certain price range. Pricing - shares that are priced higher will find fewer buyers, because it makes it harder to buy round lots (100 shares at $100/share is $10,000 while at $10/share it's only $1000).  While not everyone buys stock in lots, it's important if you do anything with (standardized) options on the stock because they are always acting on lots.  In addition, even if you don't buy round lots a higher price makes it harder to buy in for a specific amount because each unit share has a greater chance to be further away from your target amount. Conversely, shares that are priced too low will also find fewer buyers, because some holders have minimum price requirements due to low price (e.g. penny) stocks tending to be more speculative and volatile. So, different funds tracking the same index might pick different price points to satisfy demand that is not being filled by other funds selling at a different price point." "As other people have posted starting with ""fictional money"" is the best way to test a strategy, learn about the platform you are using, etc. That being said I would about how Fundamental Analysis works . Fundamental Analysis is the very basis of learning about an assets true value is priced. However in my humble opinion, I personally just stick with Index funds. In layman's terms Index Funds are essentially computer programs that buy or sell the underlying assets based on the Index they are associated with in the portion of the underlying index. Therefore you will usually be doing as good or as bad as the market. I personally have the background, education, and skillsets to build very complex models to do fundamental analysis but even I invest primarily in index funds because a well made and well researched stock model could take 8 hours or more and Modern Portfolio Theory would suggest that most investors will inevitably have a regression to the mean and have gains equal to the market rate or return over time. Which is what an index fund already does but without the hours of work and transaction cost." "I think this question is perfectly on topic, and probably has been asked and answered many times.  However, I cannot help myself. Here are some basics however: Personal Finance is not only about math.  As a guy who ""took vector calculus just for fun"", I have learned that superior math skills do not translate into superior net worth.  Personal finance is about 50% behavior.  Take a look at the housing crisis, car loans, or payday lenders and you will understand that the desire to be accepted by others often trumps the math surrounding a transaction. Outline your goals  What is it that you want in life?  A pile of money or to retire early?  What does your business look like?  How much cash will you need?  Do you want to own a ton of rental properties?  How does all this happen (set intermediate goals). Then get on a budget  A budget is a plan to spend your money in advance.  Stick to it.  From there you can see how much money you have to implement various goals.  Are your goals to aggressive?   This is really important as people have a tendency to spend more money then they have.  Often times when people receive a bonus at work, they spend that one bonus on two or three times over.  A budget will prevent this from happening. Get an Emergency Fund  Without an emergency fund, you be subject to the financial whims of people involved in your own life and that of the broader marketplace.  Once you have one, you are free to invest with impunity and have less stress in a world that deals out plenty.  Bad things will happen to you financially, protect against them. The best first investments are simple:  Invest in yourself.  Find a way to make a very healthy income with upward mobility.  Also get out and stay out of debt.  These things are not sexy, but they pay off in the long run. The next best investment is also simple:  Index funds.  These become the bench mark for all other investments.  If you do not stand a good chance of beating the S&P 500 index fund, why bother?  Just dump the money in the fund and sleep well at night." "Answering a more general question:  are financial services firms worth the money?  It really depends on the person.  Some can contribute regularly to index funds, and do the asset allocation on their own.  They are comfortable buying and selling various funds and there is really not that much management to do a Bogle like ""3 fund portfolio"".  All that is needed is an occasional re-balance.  This person probably does not need a firm like UBS or many of the others out there. Some do some active picking of funds and stocks, and also some indexing.  Again they are comfortable in doing the right thing and probably don't need a manager. There are others, however, that need a manager.  A friend of mine pulled all of his money out of the market when Trump was elected.  He missed out on some nice growth.  The extra percentage point that he paid to have an adviser would have been well worth it. For people who get spooked easily by the market and need things explained over and over, an advisory service is great.  My mom falls in that category.  I thank God every day for her service as she would otherwise call me with the same investment questions every other quarter." Warren Buffet and Berkshire Hathaway took a 50% loss in each of the last two bear markets. His stock even lost 10% in 2015 when the S&P lost 8%. He doesn't have a track record to support the claim that his stock performs relatively better in a bear market, so perhaps it's best to take his letter with a grain of salt. Edit: As one commenter points out, Mr. Buffett is comparing the book performance of his fund to the market performance of an index. That is an apples to oranges comparison. It's deceptive at best. "Remember that in most news outlets journalists do not get to pick the titles of their articles.  That's up to the editor.  So even though the article was primarily about ETFs, the reporter made the mistake of including some tangential references to mutual funds.  The editor then saw that the article talked about ETFs and mutual funds and -- knowing even less about the subject matter than the reporter, but recognizing that more readers' eyeballs would be attracted to a headline about mutual funds than to a headline about ETFs -- went with the ""shocking"" headline about the former. In any case, as you already pointed out, ETFs need to know their value throughout the day, as do the investors in that ETF.  Even momentary outages of price sources can be disastrous. Although mutual funds do not generally make transactions throughout the day, and fund investors are not typically interested in the fund's NAV more than once per day, the fund managers don't just sit around all day doing nothing and then press a couple buttons before the market closes.  They do watch their NAV very closely during the day and think very carefully about which buttons to press at the end of the day.  If their source of stock price data goes offline, then they're impacted almost as severely as -- if less visibly than -- an ETF. Asking Yahoo for prices seems straightforward, but (1) you get what you pay for, and (2) these fund companies are built on massive automated infrastructures that expect to receive their data from a certain source in a certain way at a certain time.  (And they pay a lot of money in order to be able to expect that.)  It would be quite difficult to just feed in manual data, although in the end I suspect some of these companies did just that.  Either they fell back to a secondary data supplier, or they manually constructed datasets for their programs to consume." Dogma always disappoints.  The notion that an index fund is the end-all, be-all for investing because the expense ratios are low is a flawed one. I don't concern myself with cost as an independent factor -- I look for the best value.  Bogle's dogma lines up with his business, so you need to factor that in as well. Vendors of any product spend alot of time and money convincing you that unique attributes of their product are the most important thing in the world.  Pre-crash, the dogmatics among us were bleating about how Fixed-date Retirement Funds were the new paradigm. Where did they go? "Yes. The definition of unreasonable shows as ""not guided by or based on good sense."" 100% years require a high risk. Can your one stock double, or even go up three fold? Sure, but that would likely be a small part of your portfolio. Overall, long term, you are not likely to beat the market by such high numbers.  That said, I had 2 years of returns well over 100%. 1998, and 1999. The S&P was up 26.7% and 19.5%, and I was very leverage in high tech stock options. As others mentioned, leverage was key. (Mark used the term 'gearing' which I think is leverage). When 2000 started crashing, I had taken enough off the table to end the year down 12% vs the S&P -10%, but this was down from a near 50% gain in Q1 of that year. As the crash continued, I was no longer leveraged and haven't been since. The last 12 years or so, I've happily lagged the S&P by a few basis points (.04-.02%).  Also note, Buffet has returned an amazing 15.9%/yr on average for the last 30 years (vs the S&P 11.4%). 16% is far from 100%. The last 10 year, however, his return was a modest 8.6%, just .1% above the S&P."