What Is an Index Fund?

Index funds are considered to be passively managed. The manager of an index fund tries to mimic the returns of the index it follows by purchasing all (or almost all) of the holdings in the index. Hundreds of market indexes can be invested in via mutual funds and exchange-traded funds.

What Is an Actively Managed Fund?

The portfolio manager of an actively managed fund tries to beat the market by picking and choosing investments. The manager performs an in-depth analysis of many investments to outperform the market index, like the S&P 500.

Should You Own Index Funds or Actively Managed Funds?

The potential to outperform the market is one advantage that actively managed funds have over index funds, and this notion of outperformance is attractive to investors. After all, why settle for an index fund when you know you will only receive the market return, less a nominal fee to the fund’s manager? Unfortunately, evidence that actively managed funds can consistently outperform their relevant index is difficult to find. It’s even more challenging for an individual investor to identify which actively managed fund will outperform the index in a given year. According to Vanguard, in a study of index funds versus active funds, for the 10 years ending June 30, 2020, a total of 180 of 205 Vanguard funds outperformed their peer-group averages.

9 of 9 Vanguard money market funds57 of 66 Vanguard bond funds22 of 23 Vanguard balanced funds92 of 107 Vanguard stock funds

Keep in mind, however, that most, not all, of Vanguard funds are index funds. Still, these results show the long-term advantage of passive investing versus active investing.

Active Management: Luck or Skill?

You might point out that some funds indeed beat their indexes, so why not buy those? How do we know whether the active manager was skilled in their investment selection or was just lucky? Evidence from a Barclays study shows that the chance for continued outperformance is slim for an active manager to continue beating the index.

Index Funds vs. Active Funds: Cost

Actively managed funds start at a disadvantage when compared to index funds. The average ongoing management expense of an actively managed fund costs 1% more than its passively managed cousin. The expense issue is one reason why actively managed funds underperform their index.

Index Funds vs. Active Funds: Tax-Efficiency

Another issue, which is not reflected in fund return numbers, is that the portfolio manager of an actively managed fund—in search of higher returns—buys and sells investments more frequently than an index fund does. This buying and selling of stocks by the active manager—known as “turnover”—results in taxable capital gains to the fund shareholders, provided the fund is owned in a non-retirement account.

Bottom Line

As with any investment decision, the best type of fund to buy depends on the individual’s circumstances and financial objectives. While history shows that there are good active managers, finding such managers in advance of their outperformance is difficult. Since index funds have historically beaten the majority actively managed funds for periods of 10 years or more, long-term investors should seriously consider passive investing.