| Date | Value |
|---|---|
| Mar 21, 2020 20:16 | 0.00 ppm |
| Mar 4, 2020 00:30 | 0.00 ppm |
| Feb 29, 2020 23:31 | 1.5 ppm |
| Feb 28, 2020 00:45 | 0.25 ppm |
| Feb 25, 2020 23:58 | 4 ppm |
| Feb 24, 2020 01:40 | 2 ppm |
| Feb 21, 2020 00:36 | 2 ppm |
| Feb 18, 2020 23:55 | 3 ppm |
| Feb 17, 2020 19:11 | 2 ppm |
| Feb 15, 2020 03:53 | 1.8 ppm |
| Feb 12, 2020 23:40 | 2 ppm |
| Feb 10, 2020 22:50 | 1 ppm |
| Feb 9, 2020 01:16 | 1 ppm |