How many charts can you track?

Steve DaumMost of our customers use charts as part of their work. Depending on their job, they may review charts every hour, day, week, or at some other interval. Creating and reviewing these charts is almost never a primary job. Instead, the charts are used as decision support tools; they support the primary job and help a user make better decisions.

Different types of charts have different usage patterns. For example, when looking at a chart of sales, the usage pattern is something like this:

  1. View the chart
  2. Ask this question: Are we on target, above target, or below target?
  3. Depending on the answer, take appropriate action to move towards the desired outcome.
  4. At some later date, repeat.

Statistical process control (SPC) charts have a similar usage pattern with a narrower focus. For example, you might chart the wait time between a customer posting an order and receiving an order acknowledgement.

Still, control charts follow a usage pattern:

  1. View the chart
  2. Look for evidence that anything is changing;
    1. Is the process stable?
    2. Is the process degrading?
    3. Is the process improving?
    4. Depending on the answers, take action to move towards improvement
    5. At some later time, repeat

Both of these chart usage patterns might be simplified as repetitions of:

  1. View
  2. Evaluate
  3. Act

Like many activities that we repeat over time, we can get really good at this. We become so efficient that we glance at a chart and have the evaluation done in seconds. Deciding what action to take may be done in a few minutes. Then we move on to other activities like producing product, providing service, or planning the next production line upgrade.

There is not much friction with this pattern for a single chart. What happens when there are 10 important charts? What happens when there are dozens or hundreds of important charts?

Once you see the benefit of using a control chart for one metric, it is common that you will see the benefit of using control charts for additional metrics. This will lead to a large number of control charts. The question is, “How do you handle the View, Evaluate, Act pattern for all of these charts and continue to do your primary work?”

PQ Systems has been thinking hard about this question. We’ve provided SPC charting software for over 20 years. We’ve seen these challenges play out among our customers. We have designed a new application to resolve this control chart scalability problem: CHARTrunner-m.

The CHARTrunner-m approach is to automate much of the work in View, and Evaluate and some of the work in Act. By delegating this work to CHARTrunner-m, we free up workers to pay attention to more charts without investing more of their time. Workers still get involved it the critical Act part of the pattern. Judgment and knowledge about how the process operates will always temper any action that gets taken. People are good at this, so they are still involved. CHARTrunner-m handles the tedium of chart generation and chart interpretation, then sends email or text messages only when a signal is detected that requires judgment from a worker.

How many control charts can you track?

To learn more about CHARTrunner-m visit: