Calculated Percentages of Out-of-Control (OOC) Data Points Exceeding the Upper (UCL) and Lower (LCL) Three-sigma Control Limits in Poisson and XmR Charts of Computer-Generated Random 10000 Data from a Poisson Distribution with Various μ Values
| Formal Action Limit | Expected Average Count (μ) | % OOC Data | |||||
|---|---|---|---|---|---|---|---|
| Poisson | XmR | ||||||
| Below LCL | Above UCL | Total | Below LCL | Above UCL | Total | ||
| 5 | 1 | 0 | 170 | 1.7 | 0 | 170 | 1.7 |
| 10 | 4 | 0 | 62 | 0.62 | 0 | 62 | 0.62 |
| 25 | 13 | 3 | 42 | 0.45 | 3 | 42 | 0.45 |
| 50 | 30 | 5 | 23 | 0.28 | 5 | 23 | 0.28 |
| 100 | 70 | 5 | 21 | 0.26 | 5 | 21 | 0.26 |
| 200 | 160 | 9 | 19 | 0.28 | 14 | 19 | 0.33 |