Understanding and using Bullet Graphs
How do I read it?
A bullet graph consists of a bar representing the featured measure. This bar stands out from the rest of the graph with its strong color and bold line. It positions itself in the middle of the graph. A reference line, denoting a goal or other critical threshold, is set perpendicular to the bar on the axis with the quantitative scale. When the main bar passes the reference line the goal has been met or the state has changed.
The use of shading, color, or lines in and around the featured measure add context. These can show previous performance, goals, forecasts, or highlight more dimensions. These allow for one display to enable concurrent monitoring and exploration. For example, suppose someone uses a bar graph to track expenses year over year. The graph allows them to check whether year-to-date expenses are below last year’s at a glance. Reference lines or shading enable the creation of thresholds based on previous data. They would then check to make sure the featured measure remains below the threshold.