| Year | Protected | Not Protected | Protected % |
| 2015 | 0 | 34 | 0.00 |
| 2006 | 17 | 19 | 47.22 |
| 2004 | 32 | 12 | 72.73 |
| 2014 | 0 | 34 | 0.00 |
| 2009 | 0 | 34 | 0.00 |
| 2007 | 5 | 28 | 15.15 |
| 2013 | 0 | 34 | 0.00 |
| 2008 | 0 | 34 | 0.00 |
| 1998 | 0 | 15 | 0.00 |
| 2012 | 0 | 34 | 0.00 |
| 2001 | 7 | 26 | 21.21 |
| 2011 | 0 | 34 | 0.00 |
| 2003 | 36 | 6 | 85.71 |
| 2010 | 0 | 33 | 0.00 |
| 2002 | 34 | 4 | 89.47 |
| 2000 | 4 | 24 | 14.29 |
| 2005 | 13 | 32 | 28.89 |
| 1999 | 1 | 21 | 4.55 |
| Totals | 149 | 458 | 24.55 |