| Date | Value |
|---|---|
| Mar 11, 2015 03:07 | 2 ppm |
| Mar 11, 2015 03:07 | 2 ppm |
| Mar 1, 2015 15:30 | 1 ppm |
| Feb 15, 2015 07:03 | 2 ppm |
| Jan 18, 2015 17:31 | 5 ppm |
| Jan 15, 2015 17:37 | 5 ppm |
| Jan 12, 2015 09:17 | 5 ppm |
| Jan 4, 2015 13:09 | 10 ppm |
| Dec 27, 2014 12:54 | 10 ppm |
| Dec 23, 2014 16:03 | 10 ppm |