| Year | Protected | Not Protected | Protected % |
| 2005 | 0 | 41 | 0.00 |
| 2006 | 21 | 20 | 51.22 |
| 2007 | 0 | 31 | 0.00 |
| 2008 | 0 | 31 | 0.00 |
| 2009 | 0 | 32 | 0.00 |
| 2010 | 0 | 32 | 0.00 |
| 2011 | 0 | 32 | 0.00 |
| 2012 | 0 | 33 | 0.00 |
| 2013 | 0 | 33 | 0.00 |
| 2014 | 0 | 34 | 0.00 |
| 2015 | 0 | 34 | 0.00 |
| 2016 | 0 | 35 | 0.00 |
| 2017 | 0 | 36 | 0.00 |
| 2018 | 0 | 37 | 0.00 |
| Totals | 21 | 461 | 4.36 |