Control charts usually present a graphic display of process stability and/or instability with time, from which the you can determine mean and standard deviation.

How to calculate Standard Deviation in Excel The Standard Deviation is a term used in statistics. The term describes how much the numbers if a set of data vary from the mean.

How to Make a Graph on Excel With a Cumulative Average. A cumulative average recalculates a data set's average as new data is added. During the recalculation all data contained in the data set is ...