| Date | Value |
|---|---|
| Jan 16, 2015 21:19 | 1380 ppm |
| Nov 23, 2014 03:40 | 1290 ppm |
| Nov 20, 2014 20:31 | 1170 ppm |
| Nov 11, 2014 21:16 | 1500 ppm |
| Sep 29, 2014 09:52 | 1275 ppm |
| Sep 14, 2014 10:04 | 1260 ppm |
| Sep 13, 2014 11:17 | 1200 ppm |
| Sep 3, 2014 11:14 | 1200 ppm |
| Aug 26, 2014 09:24 | 1200 ppm |
| Sep 20, 2012 22:09 | 1290 ppm |