| Year | Protected | Not Protected | Protected % |
| 2001 | 0 | 28 | 0.00 |
| 2002 | 34 | 0 | 100.00 |
| 2003 | 39 | 0 | 100.00 |
| 2004 | 40 | 0 | 100.00 |
| 2005 | 41 | 0 | 100.00 |
| 2006 | 36 | 5 | 87.80 |
| 2007 | 31 | 0 | 100.00 |
| 2008 | 31 | 0 | 100.00 |
| 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 | 34 | 0 | 100.00 |
| 2015 | 34 | 0 | 100.00 |
| 2016 | 32 | 3 | 91.43 |
| 2017 | 8 | 28 | 22.22 |
| 2018 | 0 | 37 | 0.00 |
| 2019 | 0 | 38 | 0.00 |
| 2020 | 0 | 39 | 0.00 |
| 2021 | 0 | 30 | 0.00 |
| 2022 | 0 | 41 | 0.00 |
| 2023 | 0 | 42 | 0.00 |
| 2024 | 0 | 42 | 0.00 |
| Totals | 522 | 333 | 61.05 |