Table of Contents

Median

The median is the number that sits right in the middle of a set of data when that data is arranged in order from smallest to largest. Imagine lining up a group of people by height; the median height is the height of the person standing in the exact middle. Unlike its more famous cousin, the mean (or average), the median isn't swayed by extreme values, known as outliers. This resilience makes it an incredibly powerful and honest tool for investors. If you have five companies with profits of $1 million, $2 million, $3 million, $4 million, and $100 million, the average profit is a whopping $22 million. This figure is heavily distorted by the one superstar company. The median, however, is simply the middle value: a much more representative $3 million. It gives you a truer sense of what a “typical” company in that group looks like, which is a cornerstone of sound investment analysis.

Why the Median Matters in Investing

For a value investor, reality is everything. We want to understand a business or a market for what it truly is, not what a few exceptions make it seem to be. The median helps us cut through the noise and find that reality. Averages can be deceptive, painting a picture that is rosier—or sometimes gloomier—than the truth. The median acts as a reliable anchor, providing a more stable and realistic viewpoint.

Median vs. Mean: The Skew Showdown

The biggest selling point of the median is its performance in a skewed distribution—that is, a dataset where a few extremely high or low numbers pull the average in their direction. Let's see this with a simple example. Imagine you're analyzing the salaries at a small company to gauge its compensation structure. There are 5 employees:

The mean (average) salary is ($50,000 + $55,000 + $60,000 + $65,000 + $1,000,000) / 5 = $246,000. If you were told the “average” salary is $246,000, you'd think it's a very high-paying company for everyone. Now, let's find the median. First, we sort the numbers (they already are). The middle value is $60,000. This figure gives you a much more accurate idea of what a typical employee earns. The CEO's massive salary is an outlier that wildly skews the mean but has no effect on the median. Pro tip: If the median and mean of a dataset are far apart, it's a huge red flag telling you to investigate for outliers that might be distorting the bigger picture.

Practical Applications for the Value Investor

Understanding the median isn't just a fun math trick; it has direct, money-making applications.

Analyzing Financial Ratios

When you're comparing a company to its peers, using the industry's median financial ratios is often more insightful than using the average.

Understanding Economic Data

When you read about the economy, pay close attention to whether journalists and analysts are using mean or median figures.