| Date | Value |
|---|---|
| Jan 11, 2019 11:04 | 1455 ppm |
| Jan 9, 2019 23:24 | 1425 ppm |
| Dec 15, 2017 12:24 | 1260 ppm |
| Apr 10, 2017 22:26 | 1410 ppm |
| Apr 8, 2017 16:16 | 1380 ppm |
| Apr 7, 2017 16:48 | 1410 ppm |
| Apr 3, 2017 15:29 | 1350 ppm |
| Apr 2, 2017 15:29 | 1350 ppm |
| Apr 1, 2017 15:29 | 1350 ppm |
| Mar 20, 2017 15:07 | 1440 ppm |
| Mar 15, 2017 15:52 | 1400 ppm |