The plan vs. actual chart is one of the most powerful and simple visual process performance metrics. In fact, it’s a sort of Swiss Army knife of charts in that it not only provides insight into process performance but also, by the virtue of its comment field, begs and shares information as to when and why there is a variance from the plan. Ultimately, it is about problem identification.

The chart is often positioned at the pacemaker process or at the output end of a line or cell (which can be the same thing). It goes by a number of different names: production analysis board, day-by-the-hour chart, ahead or beyond chart, production control board.

Typically, the discrete time increments reflected on the chart are hourly, but this is not always appropriate, depending on the takt image (i.e., pitch) of the process. The plan should reflect the customer demand as communicated by a preset schedule, or when the resource is scheduled by downstream pull signals, the actual pulled quantity serves as the plan. In any event, the plan quantities are intended to reflect and accommodate takt time and, when appropriate, afford for standard internal changeover times.

 …