| Date | Value |
|---|---|
| Mar 9, 2015 16:50 | 0.00 ppm |
| Feb 7, 2015 11:40 | 0.00 ppm |
| Jan 30, 2015 10:29 | 0.00 ppm |
| Jan 5, 2015 14:01 | 0.00 ppm |
| Oct 30, 2014 13:21 | 0.03 ppm |
| Sep 29, 2014 10:35 | 0.00 ppm |
| Aug 29, 2014 12:14 | 0.00 ppm |
| Jul 27, 2014 09:43 | 0.06 ppm |
| May 25, 2014 10:57 | 0.00 ppm |