| Date | Value |
|---|---|
| Dec 27, 2019 17:26 | 450 ppm |
| Dec 4, 2019 21:22 | 450 ppm |
| Nov 27, 2019 23:02 | 450 ppm |
| Nov 23, 2019 22:02 | 480 ppm |
| Nov 18, 2019 22:09 | 420 ppm |
| Nov 12, 2019 20:49 | 450 ppm |
| Nov 11, 2019 17:52 | 435 ppm |
| Nov 7, 2019 21:15 | 480 ppm |
| Oct 25, 2019 21:07 | 450 ppm |
| Oct 19, 2019 15:52 | 510 ppm |