| Year | Protected | Not Protected | Protected % |
| 1998 | 0 | 10 | 0.00 |
| 1999 | 0 | 17 | 0.00 |
| 2000 | 0 | 21 | 0.00 |
| 2001 | 0 | 28 | 0.00 |
| 2002 | 0 | 34 | 0.00 |
| 2003 | 1 | 38 | 2.56 |
| 2004 | 0 | 40 | 0.00 |
| 2005 | 35 | 6 | 85.37 |
| 2006 | 14 | 27 | 34.15 |
| 2007 | 30 | 1 | 96.77 |
| 2008 | 18 | 13 | 58.06 |
| 2009 | 9 | 23 | 28.13 |
| 2010 | 2 | 30 | 6.25 |
| 2011 | 0 | 32 | 0.00 |
| 2012 | 0 | 33 | 0.00 |
| 2013 | 0 | 33 | 0.00 |
| 2014 | 0 | 34 | 0.00 |
| Totals | 109 | 420 | 20.60 |