Security Selection Doesn’t Matter—or Does It?

© Can Stock Photo / alexh

One of the staples of conventional investing wisdom is asset allocation—the choosing of broad market sectors, determines investment outcomes. Supposedly, the selection of individual securities within each sector barely matters.

We will explain where the flaw is after a little history. The theory dates back to 1986 when the Financial Analysts Journal published a paper, ‘Determinants of Portfolio Performance.’ The authors concluded that asset allocation explained 93.6% of the variation in portfolio quarterly returns.

Since then, others have concluded that as much as 100% of returns are explained by asset allocation, that security selection doesn’t matter at all.

This version of reality is convenient for some financial planners, who are thereby relieved of the work of actually researching securities and managing portfolios based on that research. If it doesn’t matter what you own, only the category, you simply need to choose your pie chart of sectors and buy stuff to fill it up!

Here is the flaw: all securities are owned all the time, by someone. If you look at the aggregate of all investors (or many investors), security selection appears not to matter. But the individual does not own all securities – and the specific selection of what he or she does own has a huge impact on outcomes.

Investor A buys a security for $100, sells it later for $25 to Investor B. Investor B holds it while it recovers to $100. One has a 75% loss, the other a 300% gain. Security selection matters. In the aggregate, the security started at $100 and ended at $100. But that leaves out the loss for one and the gain for another.

One of Warren Buffett’s earliest investors put $15,000 in, back in the 1950s. Today his name is on the home of the symphony orchestra in Omaha, a beautiful performing arts facility he donated to the community. Security selection matters.

We offer no guarantees about the outcome of our work. But we believe the selection of individual securities is the biggest factor in those outcomes. If you would like to discuss this topic or anything else at greater length, email us or call.


The opinions voiced in this material are for general information only and are not intended to provide specific advice or recommendations for any individual. All performance referenced is historical and is no guarantee of future results.

Investing involves risk, including possible loss of principal.

Asset allocation does not ensure a profit or protect against a loss.

Because of their narrow focus, sector investing will be subject to greater volatility than investing more broadly across many sectors and companies.