| Year | Protected | Not Protected | Protected % |
| 2015 | 1 | 33 | 2.94 |
| 2006 | 0 | 36 | 0.00 |
| 2004 | 5 | 39 | 11.36 |
| 2014 | 0 | 34 | 0.00 |
| 2009 | 4 | 30 | 11.76 |
| 2007 | 0 | 33 | 0.00 |
| 2013 | 0 | 34 | 0.00 |
| 2008 | 0 | 34 | 0.00 |
| 1998 | 0 | 15 | 0.00 |
| 2012 | 6 | 28 | 17.65 |
| 2018 | 0 | 34 | 0.00 |
| 2001 | 16 | 17 | 48.48 |
| 2011 | 10 | 24 | 29.41 |
| 2016 | 0 | 34 | 0.00 |
| 2003 | 4 | 38 | 9.52 |
| 2010 | 27 | 6 | 81.82 |
| 2017 | 0 | 34 | 0.00 |
| 2002 | 7 | 31 | 18.42 |
| 2000 | 12 | 16 | 42.86 |
| 2005 | 3 | 42 | 6.67 |
| 1999 | 20 | 2 | 90.91 |
| Totals | 115 | 594 | 16.22 |