| Year | Protected | Not Protected | Protected % |
| 2015 | 0 | 34 | 0.00 |
| 2006 | 33 | 3 | 91.67 |
| 2004 | 34 | 10 | 77.27 |
| 2014 | 10 | 24 | 29.41 |
| 2009 | 34 | 0 | 100.00 |
| 2007 | 33 | 0 | 100.00 |
| 2013 | 31 | 3 | 91.18 |
| 2008 | 34 | 0 | 100.00 |
| 2012 | 12 | 22 | 35.29 |
| 2001 | 0 | 33 | 0.00 |
| 2011 | 34 | 0 | 100.00 |
| 2016 | 0 | 34 | 0.00 |
| 2003 | 4 | 38 | 9.52 |
| 2010 | 33 | 0 | 100.00 |
| 2017 | 0 | 34 | 0.00 |
| 2002 | 12 | 26 | 31.58 |
| 2005 | 42 | 3 | 93.33 |
| Totals | 346 | 264 | 56.72 |