| Year | Protected | Not Protected | Protected % |
| 1998 | 10 | 0 | 100.00 |
| 1999 | 16 | 1 | 94.12 |
| 2000 | 15 | 6 | 71.43 |
| 2001 | 28 | 0 | 100.00 |
| 2002 | 33 | 1 | 97.06 |
| 2003 | 35 | 4 | 89.74 |
| 2004 | 38 | 2 | 95.00 |
| 2005 | 41 | 0 | 100.00 |
| 2006 | 32 | 9 | 78.05 |
| 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 |
| Totals | 252 | 243 | 50.91 |