Year	Number
1996	8.51063823699951
1998	15.4255323410034
2000	12.6984128952026
2002	12.1693124771118
2003	6.53266334533691
2004	12.62135887146
2005	10.1941747665405
2006	14.4927539825439
2007	18.3574886322021
2008	17.7884616851807
2009	16.5876770019531
2010	16.1137447357178
2011	18.0094795227051
2012	20.3791465759277
2013	19.9052124023438
2014	15.2380952835083
2015	20.9523811340332
2016	21.4285717010498
2017	26.6666660308838
2018	21.2264156341553
2019	22.1698112487793
2020	18.8679237365723
2021	17.9245281219482
2022	17.4528293609619