| Year | Protected | Not Protected | Protected % |
| 2000 | 0 | 21 | 0.00 |
| 2001 | 0 | 28 | 0.00 |
| 2002 | 32 | 2 | 94.12 |
| 2003 | 29 | 10 | 74.36 |
| 2004 | 31 | 9 | 77.50 |
| 2005 | 36 | 5 | 87.80 |
| 2006 | 30 | 11 | 73.17 |
| 2007 | 30 | 1 | 96.77 |
| 2008 | 31 | 0 | 100.00 |
| 2009 | 32 | 0 | 100.00 |
| 2010 | 32 | 0 | 100.00 |
| 2011 | 31 | 1 | 96.88 |
| 2012 | 30 | 3 | 90.91 |
| 2013 | 32 | 1 | 96.97 |
| 2014 | 1 | 33 | 2.94 |
| 2015 | 9 | 25 | 26.47 |
| 2016 | 0 | 35 | 0.00 |
| 2017 | 0 | 36 | 0.00 |
| 2018 | 0 | 37 | 0.00 |
| 2019 | 0 | 38 | 0.00 |
| Totals | 386 | 296 | 56.60 |