• 1991 to 1991 2
• 1992 to 1994 4
• 1995 to 1996 5
• 1997 to 1999 4
• 2000 to 2001 3
• 2002 to 2004 2
• 2005 to 2006 5
• 2007 to 2009 8
• 2010 to 2011 14
• 2012 to 2014 2
• 2015 to 2016 1
• 2017 to 2018 2