index fund

Advantages

[edit] Low costs
Because the composition of a target index is a known quantity, it costs less to run an index fund. No highly paid stock pickers or analysts are needed. Typically expense ratios of an index fund ranges from 0.15% for U.S. Large Company Indexes to 0.97% for Emerging Market Indexes. The expense ratio of the average large cap actively managed mutual fund as of 2005 is 1.36%. If a mutual fund produces 10% return before expenses, taking account of the expense ratio difference would result in an after expense return of 9.85% for the large cap index fund versus 8.64% for the actively managed large cap fund.


[edit] Simplicity
The investment objectives of index funds are easy to understand. Once an investor knows the target index of an index fund, what securities the index fund will hold can be determined directly. Managing one's index fund holdings may be as easy as rebalancing every six months or every year.


[edit] Lower turnovers
Turnover refers to the selling and buying of securities by the fund manager. Selling securities in some jurisdictions may result in capital gains tax charges, which are sometimes passed on to fund investors. Because index funds are passive investments, the turnovers are lower than actively managed funds. According to a study conducted by John Bogle over a sixteen-year period, investors get to keep only 47% of the cumulative return of the average actively managed mutual fund, but they keep 87% in a market index fund. This means $10,000 invested in the index fund grew to $90,000 vs. $49,000 in the average actively managed stock mutual fund. That is a 40% gain from the reduction of silent partners.[citation needed]


[edit] No style drift
Style drift occurs when actively managed mutual funds go outside of their described style (ie. mid-cap value, large cap income, etc) to increase returns. Such drift hurts portfolios that are built with diversification as a high priority. Drifting into other styles could reduce the overall portfolio's diversity and subsequently increase risk. With an index fund, this drift is not possible and accurate diversification of a portfolio is increased.


[edit] Disadvantages

[edit] Possible tracking error from index
Since index funds aim to match market returns, both under- and over-performance compared to the market is considered a "tracking error". For example, an inefficient index fund may generate a positive tracking error in a falling market by holding too much cash, which holds its value compared to the market.

According to The Vanguard Group, a well run S&P 500 index fund should have a tracking error of 5 basis points or less, but a Morningstar survey found an average of 38 basis points across all index funds.[5]


[edit] Cannot outperform the target index
By design, an index fund seeks to match rather than outperform the target index. Therefore, a good index fund with low tracking error will not generally outperform the index, but rather produces a rate of return similar to the index minus fund costs.


[edit] Index composition changes reduce return
Whenever an index changes, the fund is faced with the prospect of selling all the stock that has been removed from the index, and purchasing the stock that was added to the index. The S&P 500 index has a typical turnover of between 1% and 9% per year.[6]

In effect, the index, and consequently all funds tracking the index, are announcing ahead of time the trades that they are planning to make. As a result, the price of the stock that has been removed from the index tends to be driven down, and the price of stock that has been added to the index tends to be driven up, in part due to arbitrageurs, in a practice known as "index front running".[7] The index fund, however, has suffered market impact costs because they had to sell stock whose price was depressed, and buy stock whose price was inflated. These losses can be considered small, however, relative to an index fund's overall advantage gained by low costs.