Year	Number of
1989	12
1990	23
1991	24
1992	21
1993	15
1994	24
1996	17
1997	19
1998	8
1999	10
2000	12
2001	10
2002	5
2003	11
2004	7
2005	10
2006	12
2007	5
2008	4
2009	8
2010	7
2011	3
2012	9
2013	5
2014	6
2015	4
2016	4
2017	1
2018	2
2019	5
2020	2