Year	Number of
1980	59
1981	49
1982	43
1983	41
1984	37
1985	43
1986	65
1987	29
1988	29
1989	37
1990	44
1991	44
1992	26
1993	49
1994	45
1995	45
1996	31
1997	32
1998	22
1999	31
2000	43
2001	22
2002	31
2003	27
2004	34
2005	24
2006	25
2008	12
2009	16
2010	14
2011	20
2012	22
2013	22
2014	23
2015	19
2016	13
2017	30
2018	11
2019	18
2020	13