| Date | Value |
|---|---|
| Nov 19, 2019 20:39 | 1365 ppm |
| Aug 4, 2018 16:10 | 1300 ppm |
| Apr 27, 2018 14:51 | 1290 ppm |
| Mar 18, 2018 10:23 | 1305 ppm |
| Jan 26, 2018 12:44 | 1260 ppm |
| Jan 15, 2018 10:58 | 1275 ppm |
| Dec 31, 2017 21:04 | 1320 ppm |
| Dec 13, 2017 07:54 | 1300 ppm |
| Dec 8, 2017 17:48 | 1200 ppm |
| Jun 18, 2017 08:50 | 1420 ppm |
| May 16, 2017 12:15 | 1365 ppm |
| May 11, 2017 16:32 | 1200 ppm |