Tag Archives: standard deviation

We’ve been doing it all wrong!

I can hear myself saying it now: “If you count up the number of work items in each column, and keep a record of each item’s start and end date, then you can create a CFD [Cumulative Flow Diagram], control chart and histogram”. Apparently I was wrong. Apparently nearly all of us are doing it… Read More »

Standard Deviation

Let’s pretend that your data (it could be anything, but those who know Kanban might want to pretend it’s Lead Time) is: 13, 18, 13, 14, 13, 16, 14, 21,13 The control chart that results from that data looks something like this:   So what are those two red lines? What do ‘Upper Control Limit’… Read More »