Year	Number of
1989	2
1990	2
1991	2
1992	2
1993	2
1994	1
1995	1
1996	1
1997	1
1998	1
1999	1
2000	1
2001	1
2002	1
2003	2
2004	2
2005	1
2006	1
2007	1
2008	1
2009	1
2010	1
2011	1
2012	1
2013	1
2014	2
2015	2