Year	Number
1996	8.67
1997	12.38
1998	16.33
1999	12.53
2000	7.75
2001	5.64
2002	12.32
2003	6.6
2004	11.85
2005	12.7
2006	10.26
2007	6.96
2008	10.36
2009	13.44
2010	23.67
2011	21.15
2012	16.29
2013	17.84
2014	12.6
2015	17.45
2016	18.91
2017	30.72
2018	30.93
2019	35
2020	32.94