I-MR chart

individuals and moving range chart

UCL = X̄ + 2.66 · MR̄

Used when only one value per time is available, for example batch processes, destructive tests or slow processes. Sigma is estimated from the average moving range divided by 1.128.

Calculate it

Process Capability & Control Charts: Cp, Cpk, Pp, Ppk, PPM and confidence intervals with X-bar/R, X-bar/S or I-MR charts and all 8 Nelson rules.

Related terms

• X-bar R chart: control chart for subgroup means and ranges