Median

What Is a Median?

The median is the middle value in a group of numbers arranged from smallest to largest. Half of the values sit above it and half sit below it. In finance and economics, it is often used to describe a typical value when the data includes a few very large or very small numbers, because those extremes do not pull it far off center the way they can pull the arithmetic mean.

How Is the Median Calculated?

First, sort the values from lowest to highest. If there is an odd number of values, the median is the one in the exact middle. If there is an even number, the median is the average of the two values in the middle:

Median = (Middle Value 1 + Middle Value 2) ÷ 2

Consider five hypothetical household incomes: 30,000, 40,000, 45,000, 50,000 and 400,000 dollars. The middle value is 45,000 dollars, so that is the median. The mean of the same five figures is 113,000 dollars, pulled upward by a single high income that acts as an outlier.

Why It Matters to Investors

Medians appear often in market and economic reporting, such as median home prices in a region or median returns across a group of funds. Because a few extreme results can skew an average, the median can give a more representative picture of what a typical outcome looked like. Investors comparing a fund with its peers may find it useful to see where the fund's return falls relative to the group's median.

A median has limits, though. It says nothing about how widely the values are spread, which is why analysts often pair it with standard deviation or a percentile range. When a distribution is lopsided, the median and mean can diverge noticeably, a pattern tied to skewness in the data.