| Date | Value |
|---|---|
| Feb 12, 2016 15:40 | 1200 ppm |
| Dec 19, 2015 15:48 | 1335 ppm |
| Oct 10, 2015 10:05 | 1270 ppm |
| Sep 19, 2015 09:35 | 1320 ppm |
| Sep 12, 2015 19:58 | 1260 ppm |
| Aug 29, 2015 13:30 | 1200 ppm |
| Aug 11, 2015 19:44 | 1200 ppm |
| Jan 24, 2015 13:23 | 1350 ppm |
| Nov 29, 2014 12:01 | 1290 ppm |
| Apr 15, 2014 19:02 | 1320 ppm |
| Mar 14, 2014 20:11 | 1200 ppm |