The statistical process control (SPC) reports monitor the
stability of a process. The charts in the reports show the
data points in relation to the mean value, and upper and lower
control limits.

SPC - Histogram
This bar chart is an overview of the frequency of an event
or observation across a set of ranges or bins. The
y axis shows the frequency. The x axis shows the bins. The
height of the bar in a bin indicates the frequency of the
event that falls into the range.

SPC - X Bar R/S Chart
The SPC - X Bar R/S chart shows variations in a process. You can use this chart to
evaluate the stability of a process over a set of day ranges.