The middle value in a group of measurements.
In statistics, the median represents the middle value in a group of measurements. It is a commonly used indicator of what measurement is typical or normal for a group. The median is joined by the mean and the mode to create a grouping called measures of central tendency. Although the mean is used more frequently than the median, the median is still an important measure of central tendency because it is not affected by the presence or a score that is extremely high or extremely low relative to the other numbers in the group.
See also Mode
Peavy, J. Virgil. Descriptive Statistics: Measures of Central
Tendency and Dispersion. Atlanta, GA: U.S. Dept. of Health and Human Services/Public Health Service, Centers for Disease Control, 1981.
The median is 129.