Skip to Content
ETF Specialist

Survivorship Bias

Surviving funds can overstate a category's performance.

Mentioned: ,

Many funds that were around 20 years ago no longer exist. Not surprisingly, the funds that closed tended to have relatively poor performance. Fund companies have a habit of merging losers with better-performing funds, which allows them to keep their clients' assets and mask poor performance.

The average return for all mutual funds currently in the large-blend category was 8.9% annualized over the trailing 20 years through March 2014. While this statement is accurate, it overstates the performance of the average large-blend fund that existed 20 years ago because it excludes the performance of funds that did not survive the period; this phenomenon is known as survivorship bias. Additionally, some of the funds currently in the large-blend category may have been in a different category 20 years ago. This is called look-ahead bias. Look-ahead bias can occur when a fund's category is changed but those changes were not known at the beginning of the time period.

Michael Rawson does not own (actual or beneficial) shares in any of the securities mentioned above. Find out about Morningstar’s editorial policies.

Transparency is how we protect the integrity of our work and keep empowering investors to achieve their goals and dreams. And we have unwavering standards for how we keep that integrity intact, from our research and data to our policies on content and your personal data.

We’d like to share more about how we work and what drives our day-to-day business.

We sell different types of products and services to both investment professionals and individual investors. These products and services are usually sold through license agreements or subscriptions. Our investment management business generates asset-based fees, which are calculated as a percentage of assets under management. We also sell both admissions and sponsorship packages for our investment conferences and advertising on our websites and newsletters.

How we use your information depends on the product and service that you use and your relationship with us. We may use it to:

  • Verify your identity, personalize the content you receive, or create and administer your account.
  • Provide specific products and services to you, such as portfolio management or data aggregation.
  • Develop and improve features of our offerings.
  • Gear advertisements and other marketing efforts towards your interests.

To learn more about how we handle and protect your data, visit our privacy center.

Maintaining independence and editorial freedom is essential to our mission of empowering investor success. We provide a platform for our authors to report on investments fairly, accurately, and from the investor’s point of view. We also respect individual opinions––they represent the unvarnished thinking of our people and exacting analysis of our research processes. Our authors can publish views that we may or may not agree with, but they show their work, distinguish facts from opinions, and make sure their analysis is clear and in no way misleading or deceptive.

To further protect the integrity of our editorial content, we keep a strict separation between our sales teams and authors to remove any pressure or influence on our analyses and research.

Read our editorial policy to learn more about our process.