| Date | Value |
|---|---|
| Aug 14, 2014 23:32 | 0.03 ppm |
| Jul 8, 2014 17:38 | 0.01 ppm |
| Jun 10, 2014 00:10 | 0.01 ppm |
| Jun 2, 2014 23:08 | 0.03 ppm |
| Dec 31, 2013 20:55 | 0.00 ppm |
| Aug 4, 2013 03:05 | 0.00 ppm |
| Aug 1, 2013 16:21 | 0.00 ppm |
| Jul 31, 2013 15:36 | 0.00 ppm |
| Mar 13, 2013 00:02 | 0.00 ppm |