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Pareto¶
Identify which categories contribute most to a problem so you can focus improvement efforts where they matter most.
What is a Pareto Chart?¶
A Pareto chart combines a bar chart with a cumulative line to show the relative importance of different categories. The bars are arranged in descending order of frequency or magnitude, making it easy to see which categories have the biggest impact.
The chart is based on the Pareto Principle (also called the 80/20 rule), which suggests that roughly 80% of effects come from 20% of causes. In quality improvement, this means a few defect types often account for most of the problems.
When to Use a Pareto Chart¶
- When you have categorical data and want to know which categories occur most frequently
- When you need to prioritize improvement efforts by identifying the "vital few" causes
- When you want to show stakeholders where to focus resources for maximum impact
- When comparing before/after data to verify that improvements addressed the right issues
Example Output¶
A typical Pareto chart shows defect types as bars (sorted from most to least frequent) with a cumulative percentage line showing how quickly categories add up to 100%.
Negative Values in Pareto Analysis
Traditional Pareto charts are designed for non-negative data such as counts or costs. Quantum XL extends this capability by allowing negative values in continuous frequency analysis, enabling more comprehensive financial analysis where returns, refunds, or adjustments need to be factored into category rankings.
What the sheet records about your settings¶
The User input box in the top left of the worksheet does not only echo the columns you picked. Under a Settings heading it also states the options that produced the chart below it, so a sheet opened a year later says what it was built from rather than leaving you to guess which boxes were ticked.
This matters most where the choice leaves no other trace. Two Pareto charts drawn from the same data, one grouping the small categories into an "Others" bar and one dropping them, look like two different data sets unless the sheet says which was done.
Two rules decide what appears:
- Every selector and checkbox is printed on every run, whether or not you changed it from the default. A reader who sees nothing cannot tell a default from a setting the product does not report, so the box states all of them.
- A value you had to type is printed only when you typed it, and so is a setting that only means something once another box is ticked. Its absence is the answer.
The worksheet is protected¶
Under the last block in column A, in small italic text, the sheet carries one note:
This worksheet is protected to prevent accidental changes. To unprotect it, select the Review tab and then Unprotect Sheet.
Every analysis worksheet Quantum XL writes is protected, and every one carries this note. The wording is the same on all of them. Protection is there so that a click or a stray keystroke cannot overwrite a number the chart is drawn from, or move a chart off its anchor.
Three things are still allowed while the sheet is protected: formatting cells, formatting columns, and formatting rows. So you can widen a column, change a number format, or restyle a heading without unprotecting anything. Editing a value, editing a chart, and everything else are blocked.
For those, unprotect the sheet from Excel's Review tab, exactly as the note says. The protection carries no password, so Unprotect Sheet takes it straight off without asking for one.
Under Settings, this tool records two rows:
| Row | What it reads |
|---|---|
| Maximum bars | the number you set, or No limit when you left it at zero or below |
| Group into Others | On or Off |
Those two together are the whole story of what was left off the chart. Separately, when the bars are capped and grouping is Off, an orange note appears beside the chart reading Only the top 10 bars are displayed, with your own maximum in place of the 10.
Learn More¶
- How-To: Step-by-step tutorials for different scenarios
- Preparing Your Data: Data types, layouts, and the behavior matrix
- Options: All chart settings and customization options