| Date | Value |
|---|---|
| Jun 24, 2021 14:01 | 1480 ppm |
| Jun 17, 2021 19:23 | 1480 ppm |
| Jun 10, 2021 14:53 | 1500 ppm |
| Jun 5, 2021 18:55 | 1500 ppm |
| Jun 3, 2021 15:12 | 1290 ppm |
| May 24, 2021 17:46 | 1470 ppm |
| Mar 30, 2021 14:53 | 1410 ppm |
| Feb 25, 2021 14:54 | 1355 ppm |
| Feb 4, 2021 16:00 | 1320 ppm |
| Jul 21, 2020 01:04 | 1200 ppm |
| Jan 28, 2020 20:20 | 1400 ppm |