Draw a u Chart in Excel
Use u Charts when counting defects and the sample size varies
u Charts determine stability of "counted" data (e.g., errors per bill, dents in a car door, etc.) when there can be more than one defect per unit and the sample size varies.
u Chart data looks like this:
Example of a u Chart:
Uneven control limits result from the varying sample sizes.
It's Easy to Draw a u Chart in Excel Using QI Macros
QI Macros adds a new menu to Excel and provides two ways to create charts: a u Chart macro and a u Chart template:
I purchased QI Macros just to run control charts (worth the price just for that). I had NO idea what a robust product you have developed, and what an amazing bargain I was getting. File me under exceeded customer expectations.
- Scott Campbell
Create a u Chart by running a macro:
- Select your data.
- Select a u Chart on QI Macros menu.
- QI Macros will do the math and draw the chart for you.
- QI Macros will also turn any unstable points or conditions red - these should be investigated.
Create a chart using a u Chart template:
- Open a template: QI Macros > Control Chart Templates > Attribute (c,np,p,u,g,t) > u Chart
- Input your data into the yellow shaded area.
- The chart is drawn as the data is input.
- Run stability analysis using the chart tools menu.
What is the difference between defects and defective items?
Defects - u Charts
Each item can have more than one defect:
- scratches on a car door
- errors on a bill
- missing products in a shipment
Defective Items - p Charts
Each item is only counted once:
- car doors that need to be repainted
- bills that are wrong
- incomplete shipments
- Located to the right of the chart, this functionality allows you to change the multiplier. This automatically changes the y-axis value (e.g. 1, 10, 100, etc.):
- Specifically offered in the u Chart macro, you can toggle between a u Chart and a u' Chart by inputting either "False" (u Chart) or "True" (u' Chart):
Why Choose QI Macros Over Other Control Chart Software?
- Only $299 USD - less with quantity discounts
- No annual subscription fees
- Free technical support
Easy to Use
- Works right in Excel
- Create a chart in seconds
- Easy to customize & share charts
Proven and Trusted
- More than 100,000 users
- In More than 80 countries
- Five Star CNET Rating - Virus free