Two Funds Are All You Really Need

Written by Mark Kantrowitz | October 19, 2020

Individual investors love investing in a multitude of mutual funds. But, two funds are all you really need: a stock fund and a bond fund.

Too often, investors jump in and out of specialized mutual funds, chasing after last year’s or last month’s best performing sector.

This is partly caused by a fear of missing out on a hot stock. But, past performance is not a good indicator of future performance. Or, investors may have a hypothesis that a particular type of fund will do better in the future. These guesses are often wrong. Investors sometimes try to time the market, which also fails.

Asset Allocation is the Key to Better Performance

Most of the performance of an investment is due to the asset allocation, which is the mix between stocks and bonds. The individual investments do not matter as much.

Mutual funds with a higher percentage of stocks tend to have a greater return on investment, but also a greater risk of investment losses.

You can achieve any particular split between stocks and bonds by investing in just two funds, a stock fund and a bond fund.

If you want to decrease risk, you sell some of the investment in the stock fund and use the proceeds to invest more in the bond fund. If you want to increase returns, you sell some of the investment in the bond fund and use the proceeds to invest more in the stock fund.

Since stocks can appreciate faster than bonds, you may need to periodically rebalance your investment by selling stocks to maintain the desired mix of stocks and bonds. You should rebalance at least once a year.

Some people argue against rebalancing because it leads to capital gains. Instead, they prefer to use new contributions to return to the target asset allocation. However, since the investments are in a 529 plan, you don’t have to worry about tax efficiency.

You can substitute FDIC-insured certificates of deposit or high-yield savings accounts for the bond fund, if you wish. The purpose of the bond fund is to provide a low-risk return on investment.

Broad-Based Index Funds Work Best

Most mutual funds do not beat their benchmarks long-term. So, why not just invest directly in the benchmark, by using an index fund or ETF?

You don’t need to use a fund with more stocks than the S&P 500, like a total stock market index fund, since these funds all perform similarly. For example, the Vanguard Total Stock Market Index Fund ETF (VTI) increased by 24.2% in 2019, almost as much as the 25.3% increase in the S&P 500. Most of the performance of the S&P 500 and the total stock market index comes from the same set of about 70-80 stocks.

Passive index funds are better than active funds, since active management has higher fees. Minimizing costs is the keep to maximizing net returns. Active management rarely beats passively-managed funds when you take the sales charges and expense ratios into account.

Remember, the focus of a 529 plan is on long-term gains, which is where index funds excel.

Don’t Chase After Fads

Using a broad-based domestic stock fund, like the S&P 500, will help you avoid chasing after fads.

You do not need to invest in a Real Estate Investment Trust (REIT). If you own a home, you are already invested in real estate.

You also do not need to invest in foreign stocks. The U.S. stock market represents more than half of stock investment opportunities worldwide. Although foreign stocks can provide added diversification and smooth out volatility, they can also expose you to currency exchange rate risks, inflation rate risks, trade wars, lower liquidity, and political and economic disruption. After a few years of boosting investment returns by investing in foreign stocks, several 529 plans have suffered big performance drops due to high foreign stock exposure.

Limiting yourself to just two index funds will reduce the temptation to buy and sell funds to try to boost returns. It also helps that 529 plans are limited to just two investment changes per calendar year, which is enough for rebalancing.

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About the author

Mark Kantrowitz is a nationally-recognized expert on student financial aid, scholarships and student loans. His mission is to deliver practical information, advice and tools to students and their families so they can make informed decisions about planning and paying for college. Mark writes extensively about student financial aid policy. He has testified before Congress and federal/state agencies about student aid on several occasions. Mark has been quoted in more than 10,000 newspaper and magazine articles. He has written for the New York Times, Wall Street Journal, Washington Post, Reuters, Huffington Post, U.S. News & World Report, Money Magazine, Bottom Line/Personal, Forbes, Newsweek and Time Magazine. He was named a Money Hero by Money Magazine. He is the author of five bestselling books about scholarships and financial aid, including How to Appeal for More College Financial Aid, Twisdoms about Paying for College, Filing the FAFSA and Secrets to Winning a Scholarship. Mark serves on the editorial board of the Journal of Student Financial Aid and the editorial advisory board of Bottom Line/Personal (a Boardroom, Inc. publication). He is also a member of the board of trustees of the Center for Excellence in Education. Mark previously served as a member of the board of directors of the National Scholarship Providers Association. Mark is currently Publisher of PrivateStudentLoans.guru, a web site that provides students with smart borrowing tips about private student loans. Mark has served previously as publisher of the Cappex.com, Edvisors, Fastweb and FinAid web sites. He has previously been employed at Just Research, the MIT Artificial Intelligence Laboratory, Bitstream Inc. and the Planning Research Corporation. Mark is President of Cerebly, Inc. (formerly MK Consulting, Inc.), a consulting firm focused on computer science, artificial intelligence, and statistical and policy analysis. Mark is ABD on a PhD in computer science from Carnegie Mellon University (CMU). He has Bachelor of Science degrees in mathematics and philosophy from MIT and a Master of Science degree in computer science from CMU. He is also an alumnus of the Research Science Institute program established by Admiral H. G. Rickover.

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