| Year | Protected | Not Protected | Protected % |
| 2015 | 23 | 11 | 67.65 |
| 2006 | 0 | 36 | 0.00 |
| 2004 | 0 | 44 | 0.00 |
| 2014 | 37 | -3 | 108.82 |
| 2009 | 34 | 0 | 100.00 |
| 2020 | 0 | 34 | 0.00 |
| 2007 | 0 | 33 | 0.00 |
| 2013 | 34 | 0 | 100.00 |
| 2019 | 0 | 34 | 0.00 |
| 2008 | 0 | 34 | 0.00 |
| 1998 | 12 | 3 | 80.00 |
| 2012 | 34 | 0 | 100.00 |
| 2018 | 0 | 34 | 0.00 |
| 2001 | 2 | 31 | 6.06 |
| 2011 | 34 | 0 | 100.00 |
| 2016 | 0 | 34 | 0.00 |
| 2003 | 0 | 42 | 0.00 |
| 2010 | 56 | -23 | 169.70 |
| 2017 | 15 | 19 | 44.12 |
| 2002 | 0 | 38 | 0.00 |
| 2000 | 15 | 13 | 53.57 |
| 2005 | 0 | 45 | 0.00 |
| 1999 | 16 | 6 | 72.73 |
| Totals | 312 | 465 | 40.15 |