Year	Number
1996	9.04522609710693
1998	9.5
2000	9.95024871826172
2002	8.95522403717041
2003	14.4278602600098
2004	13.4615383148193
2005	11.0047845840454
2006	20.5741634368896
2007	20.5741634368896
2008	19.230770111084
2009	14.2180099487305
2010	14.6919431686401
2011	17.3708915710449
2012	20.1877937316895
2013	21.5962448120117
2014	27.4038467407227
2015	25.238094329834
2016	24.2857151031494
2017	25.7142848968506
2018	26.6666660308838
2019	24.761905670166
2020	29.0476188659668
2021	21.4285717010498
2022	20.2830181121826