XBar chart calculations

XBar chart control limits are calculated as follows:

XBar chart calculations

Control Limits calculated from

Control Limits calculated from
standard (mean ( ยต ) and
standard deviation (s ) are


NOTE: If subgroup size is variable, m is replaced with mi for ith subgroup limits. When subgroup size is variable, the control limit values will not be the same; therefore, the chart may display `city skyline' type control lines.

Data Plot Items

Descriptive Statistics

See Also

Quality Chart Formula Reference

XBar chart

XBar chart properties

Configuring an XBar chart

XBar-R chart

XBar-S chart

Moving XBar chart