| Year | Protected | Not Protected | Protected % |
| 2015 | 8 | 26 | 23.53 |
| 2006 | 0 | 36 | 0.00 |
| 2014 | 11 | 23 | 32.35 |
| 2009 | 0 | 34 | 0.00 |
| 2007 | 0 | 33 | 0.00 |
| 2013 | 0 | 34 | 0.00 |
| 2019 | 0 | 34 | 0.00 |
| 2008 | 0 | 34 | 0.00 |
| 2012 | 2 | 32 | 5.88 |
| 2018 | 0 | 34 | 0.00 |
| 2011 | 0 | 34 | 0.00 |
| 2016 | 0 | 34 | 0.00 |
| 2010 | 0 | 33 | 0.00 |
| 2017 | 0 | 34 | 0.00 |
| Totals | 21 | 455 | 4.41 |