| Year | Protected | Not Protected | Protected % |
| 2015 | 0 | 34 | 0.00 |
| 2006 | 25 | 11 | 69.44 |
| 2004 | 44 | 0 | 100.00 |
| 2014 | 0 | 34 | 0.00 |
| 2009 | 23 | 11 | 67.65 |
| 2007 | 23 | 10 | 69.70 |
| 2013 | 0 | 34 | 0.00 |
| 2008 | 22 | 12 | 64.71 |
| 1998 | 15 | 0 | 100.00 |
| 2012 | 3 | 31 | 8.82 |
| 2001 | 33 | 0 | 100.00 |
| 2011 | 21 | 13 | 61.76 |
| 2003 | 42 | 0 | 100.00 |
| 2010 | 24 | 9 | 72.73 |
| 2002 | 38 | 0 | 100.00 |
| 2000 | 28 | 0 | 100.00 |
| 2005 | 42 | 3 | 93.33 |
| 1999 | 22 | 0 | 100.00 |
| Totals | 405 | 202 | 66.72 |