| Year | Protected | Not Protected | Protected % |
| 2015 | 0 | 34 | 0.00 |
| 2006 | 17 | 19 | 47.22 |
| 2004 | 28 | 16 | 63.64 |
| 2014 | 0 | 34 | 0.00 |
| 2009 | 1 | 33 | 2.94 |
| 2020 | 0 | 34 | 0.00 |
| 2007 | 8 | 25 | 24.24 |
| 2013 | 0 | 34 | 0.00 |
| 2019 | 0 | 34 | 0.00 |
| 2008 | 3 | 31 | 8.82 |
| 2012 | 0 | 34 | 0.00 |
| 2018 | 0 | 34 | 0.00 |
| 2011 | 1 | 33 | 2.94 |
| 2016 | 0 | 34 | 0.00 |
| 2003 | 23 | 19 | 54.76 |
| 2010 | 10 | 23 | 30.30 |
| 2017 | 0 | 34 | 0.00 |
| 2002 | 0 | 38 | 0.00 |
| 2005 | 25 | 20 | 55.56 |
| Totals | 116 | 563 | 17.08 |