| Year | Protected | Not Protected | Protected % |
| 2001 | 0 | 28 | 0.00 |
| 2002 | 0 | 34 | 0.00 |
| 2003 | 1 | 38 | 2.56 |
| 2004 | 8 | 32 | 20.00 |
| 2005 | 0 | 41 | 0.00 |
| 2006 | 0 | 41 | 0.00 |
| 2007 | 0 | 31 | 0.00 |
| 2008 | 0 | 31 | 0.00 |
| 2009 | 1 | 31 | 3.13 |
| 2010 | 0 | 32 | 0.00 |
| 2011 | 0 | 32 | 0.00 |
| 2012 | 2 | 31 | 6.06 |
| 2013 | 1 | 32 | 3.03 |
| 2014 | 0 | 34 | 0.00 |
| 2015 | 1 | 33 | 2.94 |
| 2016 | 0 | 35 | 0.00 |
| 2017 | 0 | 36 | 0.00 |
| 2018 | 0 | 37 | 0.00 |
| 2019 | 0 | 38 | 0.00 |
| Totals | 14 | 647 | 2.12 |