Year	Number
1996	1.14
1997	0
1998	0.63
1999	0
2000	1
2001	0
2002	0.69
2003	1
2004	1.42
2005	1.08
2006	3.55
2007	3.15
2008	2.14
2009	2.33
2010	4.36
2011	9.22
2012	7.6
2013	3.57
2014	8.45
2015	11.35
2016	16.07
2017	20.74
2018	25.96
2019	21.81
2020	12.07