| Year | Protected | Not Protected | Protected % |
| 2006 | 10 | 26 | 27.78 |
| 2004 | 6 | 38 | 13.64 |
| 2014 | 0 | 34 | 0.00 |
| 2009 | 0 | 34 | 0.00 |
| 2007 | 11 | 22 | 33.33 |
| 2013 | 0 | 34 | 0.00 |
| 2008 | 0 | 34 | 0.00 |
| 1998 | 0 | 15 | 0.00 |
| 2012 | 0 | 34 | 0.00 |
| 2001 | 9 | 24 | 27.27 |
| 2011 | 0 | 34 | 0.00 |
| 2003 | 17 | 25 | 40.48 |
| 2010 | 5 | 28 | 15.15 |
| 2002 | 4 | 34 | 10.53 |
| 2000 | 5 | 23 | 17.86 |
| 2005 | 8 | 37 | 17.78 |
| 1999 | 0 | 22 | 0.00 |
| Totals | 75 | 498 | 13.09 |