Year	Number
1996	5.5
1998	9.95024871826172
2000	6.96517419815063
2002	7.46268653869629
2003	10.4477615356445
2004	8.65384578704834
2005	13.4615383148193
2006	13.4615383148193
2007	11.057692527771
2008	12.0192308425903
2009	11.8483409881592
2010	11.8483409881592
2011	11.7370891571045
2012	13.6150236129761
2013	15.023473739624
2014	17.2413787841797
2015	17.2413787841797
2016	15.7635469436646
2017	16.7487678527832
2018	16.5048542022705
2019	18.8405799865723
2020	18.8405799865723
2021	22.2222213745117
2022	22.7053146362305