| Year | Protected | Not Protected | Protected % |
| 1998 | 8 | 2 | 80.00 |
| 1999 | 15 | 2 | 88.24 |
| 2000 | 16 | 5 | 76.19 |
| 2001 | 23 | 5 | 82.14 |
| 2002 | 16 | 18 | 47.06 |
| 2003 | 24 | 15 | 61.54 |
| 2004 | 40 | 0 | 100.00 |
| 2005 | 40 | 1 | 97.56 |
| 2006 | 16 | 25 | 39.02 |
| 2007 | 15 | 16 | 48.39 |
| 2008 | 20 | 11 | 64.52 |
| 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 |
| 2014 | 0 | 34 | 0.00 |
| Totals | 233 | 296 | 44.05 |