| Year | Protected | Not Protected | Protected % |
| 1998 | 0 | 10 | 0.00 |
| 1999 | 14 | 3 | 82.35 |
| 2000 | 14 | 7 | 66.67 |
| 2001 | 28 | 0 | 100.00 |
| 2002 | 34 | 0 | 100.00 |
| 2003 | 39 | 0 | 100.00 |
| 2004 | 40 | 0 | 100.00 |
| 2005 | 40 | 1 | 97.56 |
| 2006 | 14 | 27 | 34.15 |
| 2007 | 21 | 10 | 67.74 |
| 2008 | 25 | 6 | 80.65 |
| 2009 | 12 | 20 | 37.50 |
| 2010 | 12 | 20 | 37.50 |
| 2011 | 0 | 32 | 0.00 |
| 2012 | 0 | 33 | 0.00 |
| 2013 | 0 | 33 | 0.00 |
| 2014 | 0 | 34 | 0.00 |
| Totals | 293 | 236 | 55.39 |