Year	Number of
1980	20
1981	26
1982	18
1983	16
1984	5
1985	8
1986	35
1987	27
1988	7
1989	13
1990	6
1991	14
1992	13
1993	7
1994	12
1995	8
1996	10
1997	6
1998	5
2002	2
2006	19
2007	3
2008	13
2009	4
2010	8
2011	2
2012	7
2013	3
2014	1
2015	7
2016	5
2017	1
2018	4
2019	10