Year	Number
1996	0.83
1997	1.27
1998	0
1999	2.19
2000	0
2001	1.67
2002	0.46
2003	0.82
2004	4.1
2005	0.74
2006	3.22
2007	3.4
2008	1.23
2009	2.35
2010	2.86
2011	2.21
2012	2.32
2013	2.31
2014	2.36
2015	4.28
2016	4.99
2017	3.13
2018	3.6
2019	4.07
2020	1.7