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76 FR 12451, Mar. 7, 2011, unless otherwise noted.
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At 90 FR 43371, Sept. 9, 2025, as required by the Congressional Review Act and Pub. L. 119-8, the Department of Energy removed the amendments to several sections in part 429 made effective on Dec. 23, 2024, at 89 FR 91163, Oct. 9, 2024. As of Sept. 9, 2025, the affected sections reverted to the Dec. 22, 2024 version.
| Degrees of freedom (from Appendix A) |
Confidence Interval | |||
|---|---|---|---|---|
| 90% | 95% | 97.5% | 99% | |
| 1 | 3.078 | 6.314 | 12.71 | 31.82 |
| 2 | 1.886 | 2.920 | 4.303 | 6.965 |
| 3 | 1.638 | 2.353 | 3.182 | 4.541 |
| 4 | 1.533 | 2.132 | 2.776 | 3.747 |
| 5 | 1.476 | 2.015 | 2.571 | 3.365 |
| 6 | 1.440 | 1.943 | 2.447 | 3.143 |
| 7 | 1.415 | 1.895 | 2.365 | 2.998 |
| 8 | 1.397 | 1.860 | 2.306 | 2.896 |
| 9 | 1.383 | 1.833 | 2.262 | 2.821 |
| 10 | 1.372 | 1.812 | 2.228 | 2.764 |
| 11 | 1.363 | 1.796 | 2.201 | 2.718 |
| 12 | 1.356 | 1.782 | 2.179 | 2.681 |
| 13 | 1.350 | 1.771 | 2.160 | 2.650 |
| 14 | 1.345 | 1.761 | 2.145 | 2.624 |
| 15 | 1.341 | 1.753 | 2.131 | 2.602 |
| 16 | 1.337 | 1.746 | 2.120 | 2.583 |
| 17 | 1.333 | 1.740 | 2.110 | 2.567 |
| 18 | 1.330 | 1.734 | 2.101 | 2.552 |
| 19 | 1.328 | 1.729 | 2.093 | 2.539 |
| 20 | 1.325 | 1.725 | 2.086 | 2.528 |
[76 FR 12451, Mar. 7, 2011; 76 FR 24780, May 2, 2011]