| Date | Value |
|---|---|
| Oct 8, 2015 00:07 | 0.50 ppm |
| May 19, 2015 06:35 | 0.25 ppm |
| May 4, 2015 07:30 | 0.50 ppm |
| Apr 17, 2015 21:34 | 0.25 ppm |
| Apr 1, 2015 02:49 | 0.25 ppm |
| Mar 29, 2015 01:49 | 0.50 ppm |
| Mar 20, 2015 23:48 | 3 ppm |
| Mar 17, 2015 22:06 | 2 ppm |
| Mar 16, 2015 02:11 | 0.10 ppm |
| Jan 28, 2015 19:08 | 0.00 ppm |
| Jan 5, 2015 01:42 | 0.00 ppm |
| Jan 2, 2015 21:30 | 0.50 ppm |
| Dec 28, 2014 20:00 | 0.00 ppm |