| Year | Protected | Not Protected | Protected % |
| 1998 | 0 | 10 | 0.00 |
| 1999 | 4 | 13 | 23.53 |
| 2000 | 18 | 3 | 85.71 |
| 2001 | 28 | 0 | 100.00 |
| 2002 | 28 | 6 | 82.35 |
| 2003 | 35 | 4 | 89.74 |
| 2004 | 23 | 17 | 57.50 |
| 2005 | 31 | 10 | 75.61 |
| 2006 | 29 | 12 | 70.73 |
| 2007 | 29 | 2 | 93.55 |
| 2008 | 8 | 23 | 25.81 |
| 2009 | 9 | 23 | 28.13 |
| 2010 | 11 | 21 | 34.38 |
| 2011 | 1 | 31 | 3.13 |
| 2012 | 0 | 33 | 0.00 |
| 2013 | 0 | 33 | 0.00 |
| 2014 | 0 | 34 | 0.00 |
| 2015 | 0 | 34 | 0.00 |
| Totals | 254 | 309 | 45.12 |