| Year | Protected | Not Protected | Protected % |
| 1998 | 0 | 10 | 0.00 |
| 1999 | 15 | 2 | 88.24 |
| 2000 | 20 | 1 | 95.24 |
| 2001 | 27 | 1 | 96.43 |
| 2002 | 13 | 21 | 38.24 |
| 2003 | 35 | 4 | 89.74 |
| 2004 | 37 | 3 | 92.50 |
| 2005 | 7 | 34 | 17.07 |
| 2006 | 10 | 31 | 24.39 |
| 2007 | 4 | 27 | 12.90 |
| 2008 | 0 | 31 | 0.00 |
| 2009 | 0 | 32 | 0.00 |
| 2010 | 0 | 32 | 0.00 |
| 2011 | 0 | 32 | 0.00 |
| 2012 | 0 | 33 | 0.00 |
| 2013 | 0 | 33 | 0.00 |
| 2014 | 0 | 34 | 0.00 |
| 2015 | 0 | 34 | 0.00 |
| Totals | 168 | 395 | 29.84 |