Imagine that you were only allowed one chart (or board) at the gemba. What would you pick? What is the Swiss Army knife (I'm more of a Leatherman Multitool fan myself) of charts that gives you insight into process adherence and process performance?
For me, it's the plan vs. actual chart - also known as the production analysis board (or chart), day-by-the-hour chart, etc. It is typically a paper chart (my preference) or dry erase board that is positioned at the pacemaker process. It's refreshingly low-tech and reflects, at a minimum, the line, cell or team name, output requirements (number of picks, assemblies, invoices, etc.) for the day or shift, the related takt time, the planned hourly (or smaller time increment) and cumulative outputs for the day or shift, the actual hourly and cumulative outputs (or in some practices the cumulative deficit or surplus) and fields to record the problem or reason for any hourly plan vs. actual deltas as well as a sign-off by lean leader(s) as proof of review.
So, why is the plan vs. actual so powerful? Here's 5 reasons.
- Communicates customer requirements. The chart reflects the demand, by type or product, quantity, and timing and sequence. It reflects a takt image.
- Forces the matching of cycle time to takt time. Standard work should dictate the requisite staffing (and related cycle time, work sequence and standard WIP) to satisfy the customer requirements.
- Engages the employee and drives problem-solving. Like any visual control worth its salt, the plan vs. actual is worker-managed in a relatively real-time way. It highlights abnormal conditions (hourly and/or cumulative shortfalls or overproduction) and drives self-correction or at least notification/escalation and containment. The plan vs. actual also spurs PDCA in that the worker is required to identify the root cause of the abnormal condition and ultimately points the worker, team and leadership to effective countermeasures.
- Focuses lean leaders within the context of leader standard work. A good plan vs. actual will have fields for team leader/supervisor sign-offs on the hour and managers twice daily. This is essentially proof of the execution of leader standard work in which the leader should ensure that the plan vs. actual is maintained real-time, is complete (i.e., no unexplained abnormalities), and that countermeasures are being employed in order to effectively satisfy customer requirements.
- Focuses associates and lean leaders within the context of the daily accountability process. The prior day's plan vs. actual and trended performance (including pitch logs) should be reviewed within daily tiered meetings. These meetings help drive the identification of improvement opportunities and countermeasures at the individual, team and value stream level.
So, what's your Swiss Army Knife chart and why?