| Year | Protected | Not Protected | Protected % |
| 2015 | 0 | 34 | 0.00 |
| 2006 | 21 | 15 | 58.33 |
| 2004 | 0 | 44 | 0.00 |
| 2014 | 0 | 34 | 0.00 |
| 2009 | 12 | 22 | 35.29 |
| 2020 | 0 | 34 | 0.00 |
| 2007 | 4 | 29 | 12.12 |
| 2013 | 0 | 34 | 0.00 |
| 2019 | 0 | 34 | 0.00 |
| 2008 | 3 | 31 | 8.82 |
| 1998 | 5 | 10 | 33.33 |
| 2012 | 0 | 34 | 0.00 |
| 2018 | 0 | 34 | 0.00 |
| 2001 | 0 | 33 | 0.00 |
| 2011 | 2 | 32 | 5.88 |
| 2016 | 0 | 34 | 0.00 |
| 2003 | 0 | 42 | 0.00 |
| 2010 | 5 | 28 | 15.15 |
| 2017 | 0 | 34 | 0.00 |
| 2002 | 0 | 38 | 0.00 |
| 2000 | 0 | 28 | 0.00 |
| 2005 | 19 | 26 | 42.22 |
| 1999 | 0 | 22 | 0.00 |
| Totals | 71 | 706 | 9.14 |