Quartile

A quartile is a type of statistic that splits a set of data into four equal parts, just like how a quarter represents one-fourth of a dollar. In the realm of business intelligence and data analytics, quartiles help break down a company’s data so they can understand different segments of the information. Think of it like slicing a pizza into four equal pieces so everyone gets an equal share. Each slice—or quartile—shows a different part of the data range.

The first quartile (Q1), also called the lower quartile, includes the first 25% of the data when it’s lined up from smallest to largest. The second quartile (Q2) is the median, marking the halfway point, and the third quartile (Q3), or upper quartile, contains the data point that sits three-quarters of the way through the data. Lastly, there’s the fourth quartile (Q4), which leads up to the highest value.

Businesses use quartiles to understand things like customer income levels or sales data. For example, a store might look at the quartiles of its sales data to find out which products are in the top 25% of sales (Q4) and which are in the bottom 25% (Q1). This helps them decide what to stock up on and what to promote. It’s a quick way to see how things are spread out and to make informed decisions without getting lost in the weeds of all the details.