A mutual fund is a professionally managed type of collective investment scheme that pools money from many investors and invests it in stocks, bonds, short-term money market instruments, and/or other securities. The mutual fund will have a fund manager that trades the pooled money on a regular basis. The net proceeds or losses are then typically distributed to the investors annually.
Since 1940, there have been three basic types of investment companies in the United States: open-end funds, also known in the U.S. as mutual funds; unit investment trusts (UITs); and closed-end funds. Similar funds also operate in Canada. However, in the rest of the world, mutual fund is used as a generic term for various types of collective investment vehicles, such as unit trusts, open-ended investment companies (OEICs), unitized insurance funds, and undertakings for collective investments in transferable securities (UCITS).
Massachusetts Investors Trust (now MFS Investment Management) was founded on March 21, 1924, and, after one year, it had 200 shareholders and $392,000 in assets. The entire industry, which included a few closed-end funds, represented less than $10 million in 1924.
The stock market crash of 1929 hindered the growth of mutual funds. In response to the stock market crash, Congress passed the Securities Act of 1933 and the Securities Exchange Act of 1934. These laws require that a fund be registered with the U.S. Securities and Exchange Commission (SEC) and provide prospective investors with a prospectus that contains required disclosures about the fund, the securities themselves, and fund manager. The Investment Company Act of 1940 sets forth the guidelines with which all SEC-registered funds today must comply.
With renewed confidence in the stock market, mutual funds began to blossom. By the end of the 1960s, there were approximately 270 funds with $48 billion in assets. The first retail index fund, First Index Investment Trust, was formed in 1976 and headed by John Bogle, who conceptualized many of the key tenets of the industry in his 1951 senior thesis at Princeton University. It is now called the Vanguard 500 Index Fund and is one of the world's largest mutual funds, with more than $100 billion in assets.
A key factor in mutual-fund growth was the 1975 change in the Internal Revenue Code allowing individuals to open individual retirement accounts (IRAs). Even people already enrolled in corporate pension plans could contribute a limited amount (at the time, up to $2,000 a year). Mutual funds are now popular in employer-sponsored "defined-contribution" retirement plans such as (401(k)s) and 403(b)s as well as IRAs including Roth IRAs.
As of October 2007, there are 8,015 mutual funds that belong to the Investment Company Institute (ICI), a national trade association of investment companies in the United States, with combined assets of $12.356 trillion. In early 2008, the worldwide value of all mutual funds totaled more than $26 trillion.
Mutual funds can invest in many kinds of securities. The most common are cash instruments, stock, and bonds, but there are hundreds of sub-categories. Stock funds, for instance, can invest primarily in the shares of a particular industry, such as technology or utilities. These are known as sector funds. Bond funds can vary according to risk (e.g., high-yield junk bonds or investment-grade corporate bonds), type of issuers (e.g., government agencies, corporations, or municipalities), or maturity of the bonds (short- or long-term). Both stock and bond funds can invest in primarily U.S. securities (domestic funds), both U.S. and foreign securities (global funds), or primarily foreign securities (international funds).
Most mutual funds' investment portfolios are continually adjusted under the supervision of a professional manager, who forecasts cash flows into and out of the fund by investors, as well as the future performance of investments appropriate for the fund and chooses those which he or she believes will most closely match the fund's stated investment objective. A mutual fund is administered under an advisory contract with a management company, which may hire or fire fund managers.
Mutual funds are subject to a special set of regulatory, accounting, and tax rules. In the U.S., unlike most other types of business entities, they are not taxed on their income as long as they distribute 90% of it to their shareholders and the funds meet certain diversification requirements in the Internal Revenue Code. Also, the type of income they earn is often unchanged as it passes through to the shareholders. Mutual fund distributions of tax-free municipal bond income are tax-free to the shareholder. Taxable distributions can be either ordinary income or capital gains, depending on how the fund earned those distributions. Net losses are not distributed or passed through to fund investors.
The net asset value, or NAV, is the current market value of a fund's holdings, less the fund's liabilities, usually expressed as a per-share amount. For most funds, the NAV is determined daily, after the close of trading on some specified financial exchange, but some funds update their NAV multiple times during the trading day. The public offering price, or POP, is the NAV plus a sales charge. Open-end funds sell shares at the POP and redeem shares at the NAV, and so process orders only after the NAV is determined. Closed-end funds (the shares of which are traded by investors) may trade at a higher or lower price than their NAV; this is known as a premium or discount, respectively. If a fund is divided into multiple classes of shares, each class will typically have its own NAV, reflecting differences in fees and expenses paid by the different classes.
Some mutual funds own securities which are not regularly traded on any formal exchange. These may be shares in very small or bankrupt companies; they may be derivatives; or they may be private investments in unregistered financial instruments (such as stock in a non-public company). In the absence of a public market for these securities, it is the responsibility of the fund manager to form an estimate of their value when computing the NAV. How much of a fund's assets may be invested in such securities is stated in the fund's prospectus.
US mutual funds use SEC form N-1A to report the average annual compounded rates of return for 1-year, 5-year and 10-year periods as the "average annual total return" for each fund. The following formula is used:
ERV = ending redeemable value of a hypothetical $1,000 payment made at the beginning of the 1-, 5-, or 10-year periods at the end of the 1-, 5-, or 10-year periods (or fractional portion).
Turnover is a measure of the fund's securities transactions, usually calculated over a year's time, and usually expressed as a percentage of net asset value.
This value is usually calculated as the value of all transactions (buying, selling) divided by 2 divided by the fund's total holdings; i.e., the fund counts one security sold and another one bought as one "turnover". Thus turnover measures the replacement of holdings.
In Canada, under NI 81-106 (required disclosure for investment funds) turnover ratio is calculated based on the lesser of purchases or sales divided by the average size of the portfolio (including cash).
Mutual funds bear expenses similar to other companies. The fee structure of a mutual fund can be divided into two or three main components: management fee, non-management expense, and 12b-1/non-12b-1 fees. All expenses are expressed as a percentage of the average daily net assets of the fund.
The management fee for the fund is usually synonymous with the contractual investment advisory fee charged for the management of a fund's investments. However, as many fund companies include administrative fees in the advisory fee component, when attempting to compare the total management expenses of different funds, it is helpful to define management fee as equal to the contractual advisory fee plus the contractual administrator fee. This "levels the playing field" when comparing management fee components across multiple funds.
Contractual advisory fees may be structured as "flat-rate" fees, i.e., a single fee charged to the fund, regardless of the asset size of the fund. However, many funds have contractual fees which include breakpoints so that as the value of a fund's assets increases, the advisory fee paid decreases. Another way in which the advisory fees remain competitive is by structuring the fee so that it is based on the value of all of the assets of a group or a complex of funds rather than those of a single fund.
Apart from the management fee, there are certain non-management expenses which most funds must pay. Some of the more significant (in terms of amount) non-management expenses are: transfer agent expenses (this is usually the person you get on the other end of the phone line when you want to purchase/sell shares of a fund), custodian expense (the fund's assets are kept in custody by a bank which charges a custody fee), legal/audit expense, fund accounting expense, registration expense (the SEC charges a registration fee when funds file registration statements with it), board of directors/trustees expense (the members of the board who oversee the fund are usually paid a fee for their time spent at meetings), and printing and postage expense (incurred when printing and delivering shareholder reports).
In the United States, 12b-1 service fees/shareholder servicing fees are contractual fees which a fund may charge to cover the marketing expenses of the fund. Non-12b-1 service fees are marketing/shareholder servicing fees which do not fall under SEC rule 12b-1. While funds do not have to charge the full contractual 12b-1 fee, they often do. When investing in a front-end load or no-load fund, the 12b-1 fees for the fund are usually .250% (or 25 basis points). The 12b-1 fees for back-end and level-load share classes are usually between 50 and 75 basis points but may be as much as 100 basis points. While funds are often marketed as "no-load" funds, this does not mean they do not charge a distribution expense through a different mechanism. It is expected that a fund listed on an online brokerage site will be paying for the "shelf-space" in a different manner even if not directly through a 12b-1 fee.
Fees and expenses borne by the investor vary based on the arrangement made with the investor's broker. Sales loads (or contingent deferred sales loads (CDSL)) are included in the fund's total expense ratio (TER) because they pass through the statement of operations for the fund. Additionally, funds may charge early redemption fees to discourage investors from swapping money into and out of the fund quickly, which may force the fund to make bad trades to obtain the necessary liquidity. For example, Fidelity Diversified International Fund (FDIVX) charges a 10 percent fee on money removed from the fund in less than 30 days.
An additional expense which does not pass through the statement of operations and cannot be controlled by the investor is brokerage commissions. Brokerage commissions are incorporated into the price of the fund and are reported usually 6 months after the fund's annual report in the statement of additional information. Brokerage commissions are directly related to portfolio turnover (portfolio turnover refers to the number of times the fund's assets are bought and sold over the course of a year). Usually, higher rate of portfolio turnover returns in higher brokerage commissions. The advisors of mutual fund companies are required to achieve "best execution" through brokerage arrangements so that the commissions charged to the fund will not be excessive.
The term mutual fund is the common name for what is classified as an open-end investment company by the SEC. Being open-ended means that, at the end of every day, the fund issues new shares to investors and buys back shares from investors wishing to leave the fund.
Mutual funds must be structured as corporations or trusts, such as business trusts, and any corporation or trust will be classified by the SEC as an investment company if it issues securities and primarily invests in non-government securities. An investment company will be classified by the SEC as an open-end investment company if they do not issue undivided interests in specified securities (the defining characteristic of unit investment trusts or UITs) and if they issue redeemable securities. Registered investment companies that are not UITs or open-end investment companies are closed-end funds. Neither UITs nor closed-end funds are mutual funds (as that term is used in the US).
A relatively recent innovation, the exchange-traded fund or ETF, is often structured as an open-end investment company. ETFs combine characteristics of both mutual funds and closed-end funds. ETFs are traded throughout the day on a stock exchange, just like closed-end funds, but at prices generally approximating the ETF's net asset value. Most ETFs are index funds and track stock market indexes. Shares are issued or redeemed by institutional investors in large blocks (typically of 50,000). Most investors purchase and sell shares through brokers in market transactions. Because the institutional investors normally purchase and redeem in in kind transactions, ETFs are more efficient than traditional mutual funds (which are continuously issuing and redeeming securities and, to effect such transactions, continually buying and selling securities and maintaining liquidity positions) and therefore tend to have lower expenses.
Exchange-traded funds are also valuable for foreign investors who are often able to buy and sell securities traded on a stock market, but who, for regulatory reasons, are limited in their ability to participate in traditional U.S. mutual funds.
Equity funds, which consist mainly of stock investments, are the most common type of mutual fund. Equity funds hold 50 percent of all amounts invested in mutual funds in the United States.  Often equity funds focus investments on particular strategies and certain types of issuers.
Another distinction is made between growth funds, which invest in stocks of companies that have the potential for large capital gains, and value funds, which concentrate on stocks that are undervalued. Value stocks have historically produced higher returns; however, financial theory states this is compensation for their greater risk. Growth funds tend not to pay regular dividends. Income funds tend to be more conservative investments, with a focus on stocks that pay dividends. A balanced fund may use a combination of strategies, typically including some level of investment in bonds, to stay more conservative when it comes to risk, yet aim for some growth.
An index fund maintains investments in companies that are part of major stock (or bond) indexes, such as the S&P 500, while an actively managed fund attempts to outperform a relevant index through superior stock-picking techniques. The assets of an index fund are managed to closely approximate the performance of a particular published index. Since the composition of an index changes infrequently, an index fund manager makes fewer trades, on average, than does an active fund manager. For this reason, index funds generally have lower trading expenses than actively managed funds, and typically incur fewer short-term capital gains which must be passed on to shareholders. Additionally, index funds do not incur expenses to pay for selection of individual stocks (proprietary selection techniques, research, etc.) and deciding when to buy, hold or sell individual holdings. Instead, a fairly simple computer model can identify whatever changes are needed to bring the fund back into agreement with its target index.
Certain empirical evidence seems to illustrate that mutual funds do not beat the market and actively managed mutual funds under-perform other broad-based portfolios with similar characteristics. One study found that nearly 1,500 U.S. mutual funds under-performed the market in approximately half of the years between 1962 and 1992. Moreover, funds that performed well in the past are not able to beat the market again in the future (shown by Jensen, 1968; Grinblatt and Sheridan Titman, 1989).
Bond funds account for 18% of mutual fund assets.  Types of bond funds include term funds, which have a fixed set of time (short-, medium-, or long-term) before they mature. Municipal bond funds generally have lower returns, but have tax advantages and lower risk. High-yield bond funds invest in corporate bonds, including high-yield or junk bonds. With the potential for high yield, these bonds also come with greater risk.
Money market funds hold 26% of mutual fund assets in the United States.  Money market funds entail the least risk, as well as lower rates of return. Unlike certificates of deposit (CDs), money market shares are liquid and redeemable at any time.
Funds of funds (FoF) are mutual funds which invest in other underlying mutual funds (i.e., they are funds composed of other funds). The funds at the underlying level are typically funds which an investor can invest in individually. A fund of funds will typically charge a management fee which is smaller than that of a normal fund because it is considered a fee charged for asset allocation services. The fees charged at the underlying fund level do not pass through the statement of operations, but are usually disclosed in the fund's annual report, prospectus, or statement of additional information. The fund should be evaluated on the combination of the fund-level expenses and underlying fund expenses, as these both reduce the return to the investor.
Most FoFs invest in affiliated funds (i.e., mutual funds managed by the same advisor), although some invest in funds managed by other (unaffiliated) advisors. The cost associated with investing in an unaffiliated underlying fund is most often higher than investing in an affiliated underlying because of the investment management research involved in investing in fund advised by a different advisor. Recently, FoFs have been classified into those that are actively managed (in which the investment advisor reallocates frequently among the underlying funds in order to adjust to changing market conditions) and those that are passively managed (the investment advisor allocates assets on the basis of on an allocation model which is rebalanced on a regular basis).
The design of FoFs is structured in such a way as to provide a ready mix of mutual funds for investors who are unable to or unwilling to determine their own asset allocation model. Fund companies such as TIAA-CREF, American Century Investments, Vanguard, and Fidelity have also entered this market to provide investors with these options and take the "guess work" out of selecting funds. The allocation mixes usually vary by the time the investor would like to retire: 2020, 2030, 2050, etc. The more distant the target retirement date, the more aggressive the asset mix.
Hedge funds in the United States are pooled investment funds with loose SEC regulation, unlike mutual funds. Some hedge fund managers are required to register with SEC as investment advisers under the Investment Advisers Act.  The Act does not require an adviser to follow or avoid any particular investment strategies, nor does it require or prohibit specific investments. Hedge funds typically charge a management fee of 1% or more, plus a “performance fee” of 20% of the hedge fund's profit. There may be a "lock-up" period, during which an investor cannot cash in shares. A variation of the hedge strategy is the 130-30 fund for individual investors.
Mutual funds offer several advantages over investing in individual stocks. For example, the transaction costs are divided among all the mutual fund shareholders, which allows for cost-effective diversification. Investors may also benefit by having a third party (professional fund managers) apply expertise and dedicate time to manage and research investment options, although there is dispute over whether professional fund managers can, on average, outperform simple index funds that mimic public indexes. Yet, the Wall Street Journal reported that separately managed accounts (SMA or SMAs) performed better than mutual funds in 22 of 25 categories from 2006 to 2008. This included beating mutual funds performance in 2008, a tough year in which the global stock market lost US$21 trillion in value.   In the story, Morningstar, Inc said SMAs outperformed mutual funds in 25 of 36 stock and bond market categories. Whether actively managed or passively indexed, mutual funds are not immune to risks. They share the same risks associated with the investments made. If the fund invests primarily in stocks, it is usually subject to the same ups and downs and risks as the stock market.
Many mutual funds offer more than one class of shares. For example, you may have seen a fund that offers "Class A" and "Class B" shares. Each class will invest in the same pool (or investment portfolio) of securities and will have the same investment objectives and policies. But each class will have different shareholder services and/or distribution arrangements with different fees and expenses. These differences are supposed to reflect different costs involved in servicing investors in various classes; for example, one class may be sold through brokers with a front-end load, and another class may be sold direct to the public with no load but a "12b-1 fee" included in the class's expenses (sometimes referred to as "Class C" shares). Still a third class might have a minimum investment of $10,000,000 and be available only to financial institutions (a so-called "institutional" share class). In some cases, by aggregating regular investments made by many individuals, a retirement plan (such as a 401(k) plan) may qualify to purchase "institutional" shares (and gain the benefit of their typically lower expense ratios) even though no members of the plan would qualify individually. As a result, each class will likely have different performance results. 
A multi-class structure offers investors the ability to select a fee and expense structure that is most appropriate for their investment goals (including the length of time that they expect to remain invested in the fund). 
A front-end load or sales charge is a commission paid to a broker by a mutual fund when shares are purchased, taken as a percentage of funds invested. The value of the investment is reduced by the amount of the load. Some funds have a deferred sales charge or back-end load. In this type of fund an investor pays no sales charge when purchasing shares, but will pay a commission out of the proceeds when shares are redeemed depending on how long they are held. Another derivative structure is a level-load fund, in which no sales charge is paid when buying the fund, but a back-end load may be charged if the shares purchased are sold within a year.
Load funds are sold through financial intermediaries such as brokers, financial planners, and other types of registered representatives who charge a commission for their services. Shares of front-end load funds are frequently eligible for breakpoints (i.e., a reduction in the commission paid) based on a number of variables. These include other accounts in the same fund family held by the investor or various family members, or committing to buy more of the fund within a set period of time in return for a lower commission "today".
It is possible to buy many mutual funds without paying a sales charge. These are called no-load funds. In addition to being available from the fund company itself, no-load funds may be sold by some discount brokers for a flat transaction fee or even no fee at all. (This does not necessarily mean that the broker is not compensated for the transaction; in such cases, the fund may pay brokers' commissions out of "distribution and marketing" expenses rather than a specific sales charge. The purchaser is therefore paying the fee indirectly through the fund's expenses deducted from profits.)
No-load funds include both index funds and actively managed funds. The largest mutual fund families selling no-load index funds are Vanguard and Fidelity, though there are a number of smaller mutual fund families with no-load funds as well. Expense ratios in some no-load index funds are less than 0.2% per year versus the typical actively managed fund's expense ratio of about 1.5% per year. Load funds usually have even higher expense ratios when the load is considered. The expense ratio is the anticipated annual cost to the investor of holding shares of the fund. For example, on a $100,000 investment, an expense ratio of 0.2% means $200 of annual expense, while a 1.5% expense ratio would result in $1,500 of annual expense. These expenses are before any sales commissions paid to purchase the mutual fund.
Many fee-only financial advisors strongly suggest no-load funds such as index funds. If the advisor is not of the fee-only type but is instead compensated by commissions, the advisor may have a conflict of interest in selling high-commission load funds.