| Year | Protected | Not Protected | Protected % |
| 2015 | 0 | 34 | 0.00 |
| 2006 | 5 | 31 | 13.89 |
| 2004 | 37 | 7 | 84.09 |
| 2014 | 0 | 34 | 0.00 |
| 2009 | 0 | 34 | 0.00 |
| 2007 | 0 | 33 | 0.00 |
| 2013 | 0 | 34 | 0.00 |
| 2008 | 0 | 34 | 0.00 |
| 1998 | 0 | 15 | 0.00 |
| 2012 | 0 | 34 | 0.00 |
| 2001 | 28 | 5 | 84.85 |
| 2011 | 0 | 34 | 0.00 |
| 2003 | 31 | 11 | 73.81 |
| 2010 | 0 | 33 | 0.00 |
| 2002 | 38 | 0 | 100.00 |
| 2000 | 19 | 9 | 67.86 |
| 2005 | 32 | 13 | 71.11 |
| 1999 | 16 | 6 | 72.73 |
| Totals | 206 | 401 | 33.94 |