| Date | Value |
|---|---|
| Jul 1, 2015 20:17 | 0.02 ppm |
| Feb 21, 2015 14:46 | 0.00 ppm |
| Sep 29, 2014 21:15 | 0.00 ppm |
| Aug 28, 2014 19:09 | 0.00 ppm |
| Jul 11, 2014 20:48 | 0.00 ppm |
| Jun 1, 2014 20:02 | 0.00 ppm |
| May 26, 2014 20:51 | 0.00 ppm |
| May 22, 2014 20:20 | 0.00 ppm |
| May 11, 2014 22:04 | 0.00 ppm |
| May 9, 2014 18:42 | 0.00 ppm |
| May 8, 2014 20:51 | 0.05 ppm |
| May 4, 2014 21:05 | 0.15 ppm |
| May 2, 2014 23:07 | 0.25 ppm |