A bullet chart is a graphical representation of comparative data in the form of vertical or horizontal rectangles containing line segments and stacked bars. The graphs use quantitative scales and line segments to show two or more datasets. These graphs are individual objects and are labeled in accordance with the data they represent.
Bullet charts were created to accomplish two things: replace the common gauge and offer more complexity within the bar chart design. Gauges suffer from limitations in scope, and limitations in practical, large-scale (or frequent) usage. Standard bar charts have a limited scope of expression, and variants often overload them with information.
A bullet graph is similar to the gauges it was created to replace. It has a quantitative scale, which is presented on an x or y axis. This provides information about the range of units being used, and the quantities being expressed. It has a center line segment that provides data. The line segment is located in its center and extends to its top when the chart is vertical, and to its right when the chart is horizontal. This segment represents the measure of the bullet chart that is the focus of the graph, or rather the “reading.” There is also another line segment, which is a short “tick” mark that is perpendicular to the center line. It represents the measure used for comparison. It also has a qualitative range, which is expressed through color-coded stacked bars. This provides information about measures within categorized qualitative ranges, e.g., bad, okay, and amazing.
Bullet charts have applications in many sectors and disciplines, but perhaps one of their most popular uses is the expression of financial data. Various business metrics are more clearly articulated with these gauges. They are very easy to produce and maintain, and they do not suffer from issues with clarity like other options.