| Year | Protected | Not Protected | Protected % |
| 2004 | 0 | 40 | 0.00 |
| 2005 | 23 | 18 | 56.10 |
| 2006 | 1 | 40 | 2.44 |
| 2007 | 0 | 31 | 0.00 |
| 2008 | 0 | 31 | 0.00 |
| 2009 | 18 | 14 | 56.25 |
| 2010 | 32 | 0 | 100.00 |
| 2011 | 32 | 0 | 100.00 |
| 2012 | 32 | 1 | 96.97 |
| 2013 | 33 | 0 | 100.00 |
| 2014 | 33 | 1 | 97.06 |
| 2015 | 34 | 0 | 100.00 |
| 2016 | 35 | 0 | 100.00 |
| 2017 | 32 | 4 | 88.89 |
| 2018 | 36 | 1 | 97.30 |
| 2019 | 33 | 5 | 86.84 |
| 2020 | 38 | 1 | 97.44 |
| 2021 | 1 | 29 | 3.33 |
| 2022 | 0 | 41 | 0.00 |
| 2023 | 0 | 42 | 0.00 |
| 2024 | 0 | 42 | 0.00 |
| Totals | 413 | 341 | 54.77 |