Year	Number
1996	22.8260860443115
1998	25
2000	25
2002	18.9189186096191
2003	21.0810813903809
2004	18.9054718017578
2005	23.529411315918
2006	20.5882358551025
2007	22.3300971984863
2008	21.3592224121094
2009	24.8803825378418
2010	19.1387557983398
2011	16.1137447357178
2012	17.0616111755371
2013	17.5355453491211
2014	11.5384616851807
2015	11.9047622680664
2016	10.4761905670166
2017	11.9047622680664
2018	13.3333330154419
2019	11.9047622680664
2020	11.4285717010498
2021	12.8571424484253
2022	15.5660381317139