| Date | Value |
|---|---|
| Jun 25, 2015 12:21 | 0.00 ppm |
| Jan 7, 2014 19:28 | 0.02 ppm |
| Dec 19, 2013 22:03 | 0.02 ppm |
| Nov 29, 2013 11:35 | 0.03 ppm |
| Nov 21, 2013 17:47 | 0.00 ppm |
| Oct 20, 2013 11:35 | 0.00 ppm |
| Sep 29, 2013 12:31 | 0.00 ppm |
| Aug 29, 2013 23:56 | 0.00 ppm |
| Aug 17, 2013 00:16 | 0.05 ppm |
| Aug 8, 2013 00:22 | 0.00 ppm |
| May 12, 2013 22:48 | 0.02 ppm |
| Apr 10, 2013 22:48 | 0.00 ppm |
| Mar 23, 2013 22:48 | 0.01 ppm |