| Date | Value |
|---|---|
| Aug 29, 2013 19:49 | 0.00 ppm |
| Jul 11, 2013 18:19 | 0.00 ppm |
| Jun 13, 2013 16:24 | 0.00 ppm |
| May 13, 2013 14:24 | 0.00 ppm |
| Apr 1, 2013 15:09 | 0.25 ppm |
| Mar 25, 2013 10:34 | 0.00 ppm |
| Mar 19, 2013 16:55 | 0.00 ppm |
| Mar 14, 2013 11:20 | 0.00 ppm |
| Mar 11, 2013 16:11 | 0.00 ppm |
| Feb 25, 2013 10:34 | 0.00 ppm |
| Feb 19, 2013 10:52 | 0.00 ppm |
| Feb 1, 2013 12:31 | 0.00 ppm |