| Year | Protected | Not Protected | Protected % |
| 2015 | 0 | 34 | 0.00 |
| 2006 | 0 | 36 | 0.00 |
| 2004 | 2 | 42 | 4.55 |
| 2014 | 0 | 34 | 0.00 |
| 2009 | 3 | 31 | 8.82 |
| 2020 | 0 | 34 | 0.00 |
| 2007 | 4 | 29 | 12.12 |
| 2013 | 0 | 34 | 0.00 |
| 2019 | 0 | 34 | 0.00 |
| 2008 | 1 | 33 | 2.94 |
| 2012 | 1 | 33 | 2.94 |
| 2018 | 0 | 34 | 0.00 |
| 2001 | 0 | 33 | 0.00 |
| 2011 | 2 | 32 | 5.88 |
| 2016 | 0 | 34 | 0.00 |
| 2003 | 9 | 33 | 21.43 |
| 2010 | 2 | 31 | 6.06 |
| 2017 | 0 | 34 | 0.00 |
| 2002 | 20 | 18 | 52.63 |
| 2005 | 3 | 42 | 6.67 |
| Totals | 47 | 665 | 6.60 |