A Span Chart is a visualization that shows the min. and max. Values of a category. It marks two numeric values for every category to the plot. It looks like a box, the upper edge of the box indicates maximum, whereas the lower edge of the box indicates a minimum.
Why do you need it?
Span Chart instantly shows the values of data insight. It is not suited if the middle values are the one you wants to focus on. It looks attractive and well arranged, and even it doesn’t get clustered easily.
What kind of data you can visualize with it?
It is good for categorical data, which has a min. and max. Values. Assume you have a dataset of cutting of trees for 5 years. Using Span Chart, you can see which year has maximum deforestation, and which has a minimum.