Year	Number
1996	15.5
1998	17.412935256958
2000	14.4278602600098
2002	22.3880596160889
2003	23.8805961608887
2004	19.7115383148193
2005	37.980770111084
2006	31.730770111084
2007	32.6923065185547
2008	32.211540222168
2009	32.2274894714355
2010	27.962085723877
2011	27.6995296478271
2012	27.2300472259521
2013	25.8215961456299
2014	24.630542755127
2015	20.6896553039551
2016	11.822660446167
2017	11.822660446167
2018	9.70873832702637
2019	7.24637699127197
2020	13.043478012085
2021	16.425121307373
2022	16.9082126617432