XLSTAT: Pareto Plot in Excel 

 

Background

A Pareto chart, named after economist Vilfredo Pareto and popularized by J.M. Juran in industry, displays causes (e.g., defects) sorted by frequency or impact.

XLSTAT enables creation of both basic and advanced Pareto charts, with features like multiple series, sorting, grouping, and custom colors.

 

Dataset for Example

The data are from [Pyzdek Th. (2003), The six sigma Hanbook Revised and expanded, McGraw Hill, New York] and correspond to arrival inspections of peaches of super market during 1 month.

 

Setting Up

• Open XLSTAT.

• Click on the Quality/ Statistical Process Control (SPC) menu and select the Pareto charts feature.

• The Pareto charts dialog box appears.

• In the General tab, select column A in the Root Causes field and column B in the Frequencies field. Activate the Variable Labels option.

• In the Options tab, you can sort or combine causes.

• In the Charts tab, select Frequencies to display them on the left axis of the bar chart.

• Click on the OK button to launch the computations.

• The results are displayed on a new Excel sheet.

 

Interpreting the Results

The first table displays descriptive statistics for the set of causes such as Frequency and Cumulative %.

Then the Pareto chart is displayed in the form of a bar chart.

Three defects—rotten, bruised, and undersized—account for 95% of all issues. These should be prioritized in continuous improvement efforts.