| Year | Protected | Not Protected | Protected % |
| 2004 | 0 | 40 | 0.00 |
| 2005 | 0 | 41 | 0.00 |
| 2006 | 25 | 16 | 60.98 |
| 2007 | 32 | -1 | 103.23 |
| 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 | 26 | 8 | 76.47 |
| 2016 | 7 | 28 | 20.00 |
| 2017 | 1 | 35 | 2.78 |
| 2018 | 0 | 37 | 0.00 |
| 2019 | 0 | 38 | 0.00 |
| 2020 | 0 | 39 | 0.00 |
| 2021 | 0 | 30 | 0.00 |
| Totals | 318 | 311 | 50.56 |