| Year | Protected | Not Protected | Protected % |
| 1999 | 0 | 17 | 0.00 |
| 2000 | 0 | 21 | 0.00 |
| 2001 | 0 | 28 | 0.00 |
| 2002 | 23 | 11 | 67.65 |
| 2003 | 38 | 1 | 97.44 |
| 2004 | 7 | 33 | 17.50 |
| 2005 | 32 | 9 | 78.05 |
| 2006 | 30 | 11 | 73.17 |
| 2007 | 20 | 11 | 64.52 |
| 2008 | 13 | 18 | 41.94 |
| 2009 | 16 | 16 | 50.00 |
| 2010 | 15 | 17 | 46.88 |
| 2011 | 0 | 32 | 0.00 |
| 2012 | 0 | 33 | 0.00 |
| 2013 | 0 | 33 | 0.00 |
| 2014 | 1 | 33 | 2.94 |
| 2015 | 0 | 34 | 0.00 |
| 2016 | 0 | 35 | 0.00 |
| 2017 | 0 | 36 | 0.00 |
| 2018 | 0 | 37 | 0.00 |
| Totals | 195 | 466 | 29.50 |