Year	Number
1996	12.08
1997	17.51
1998	4.5
1999	18.12
2000	15.87
2001	8.22
2002	7.65
2003	16.02
2004	20.79
2005	34.57
2006	35.42
2007	23.75
2008	39.45
2009	23.71
2010	37.2
2011	38.72
2012	30.59
2013	31.48
2014	39.31
2015	32.33
2016	41.84
2017	34.17
2018	30.24
2019	26.18
2020	35.65