Appendix C: Table of Z Values
| Confidence Level | z Factor |
| 99.9 | 3.2905 |
| 99.7 | 3.0000 |
| 99.5 | 2.8070 |
| 99.0 | 2.5758 |
| 98.0 | 2.3263 |
| 95.5 | 2.0000 |
| 95.0 | 1.9600 |
| 90.0 | 1.6449 |
| 85.0 | 1.4395 |
| 80.0 | 1.2816 |
Table taken from the Air University Sampling and Surveying Handbook, Appendix E, page 55.