| Year | Protected | Not Protected | Protected % |
| 1998 | 8 | 2 | 80.00 |
| 1999 | 17 | 0 | 100.00 |
| 2000 | 21 | 0 | 100.00 |
| 2001 | 27 | 1 | 96.43 |
| 2002 | 33 | 1 | 97.06 |
| 2003 | 37 | 2 | 94.87 |
| 2004 | 40 | 0 | 100.00 |
| 2005 | 36 | 5 | 87.80 |
| 2006 | 36 | 5 | 87.80 |
| 2007 | 31 | 0 | 100.00 |
| 2008 | 25 | 6 | 80.65 |
| 2009 | 2 | 30 | 6.25 |
| 2010 | 0 | 32 | 0.00 |
| 2011 | 0 | 32 | 0.00 |
| 2012 | 0 | 33 | 0.00 |
| 2013 | 0 | 33 | 0.00 |
| Totals | 313 | 182 | 63.23 |