| Date | Value |
|---|---|
| May 13, 2019 05:00 | 380 ppm |
| Apr 15, 2019 06:40 | 437 ppm |
| Mar 18, 2019 07:40 | 456 ppm |
| Feb 18, 2019 07:40 | 499 ppm |
| Jan 27, 2019 09:15 | 430 ppm |
| Jun 4, 2018 07:40 | 399 ppm |
| May 21, 2018 13:46 | 425 ppm |
| May 10, 2018 09:09 | 415 ppm |
| May 7, 2018 14:12 | 415 ppm |
| Apr 29, 2018 09:32 | 490 ppm |
| Apr 20, 2018 07:51 | 528 ppm |
| Apr 11, 2018 13:57 | 500 ppm |
| Apr 8, 2018 04:03 | 450 ppm |
| Apr 2, 2018 07:29 | 380 ppm |
| Mar 21, 2018 11:18 | 516 ppm |