| Year | Protected | Not Protected | Protected % |
| 2008 | 30 | 1 | 96.77 |
| 2009 | 32 | 0 | 100.00 |
| 2010 | 32 | 0 | 100.00 |
| 2011 | 32 | 0 | 100.00 |
| 2012 | 33 | 0 | 100.00 |
| 2013 | 33 | 0 | 100.00 |
| 2014 | 33 | 1 | 97.06 |
| 2015 | 36 | -2 | 105.88 |
| 2016 | 33 | 2 | 94.29 |
| 2017 | 35 | 1 | 97.22 |
| 2018 | 16 | 21 | 43.24 |
| 2019 | 0 | 38 | 0.00 |
| 2020 | 0 | 39 | 0.00 |
| 2021 | 0 | 30 | 0.00 |
| 2022 | 0 | 41 | 0.00 |
| Totals | 345 | 172 | 66.73 |