| Year | Protected | Not Protected | Protected % |
| 1999 | 0 | 17 | 0.00 |
| 2000 | 1 | 20 | 4.76 |
| 2001 | 2 | 26 | 7.14 |
| 2002 | 7 | 27 | 20.59 |
| 2003 | 1 | 38 | 2.56 |
| 2004 | 6 | 34 | 15.00 |
| 2005 | 6 | 35 | 14.63 |
| 2006 | 7 | 34 | 17.07 |
| 2007 | 9 | 22 | 29.03 |
| 2008 | 1 | 30 | 3.23 |
| 2009 | 0 | 32 | 0.00 |
| 2010 | 0 | 32 | 0.00 |
| 2011 | 0 | 32 | 0.00 |
| 2012 | 0 | 33 | 0.00 |
| 2013 | 0 | 33 | 0.00 |
| 2014 | 0 | 34 | 0.00 |
| 2015 | 0 | 34 | 0.00 |
| 2016 | 0 | 35 | 0.00 |
| Totals | 40 | 548 | 6.80 |