Year	Number
1996	19.0217399597168
1998	22.2826080322266
2000	29.3478260040283
2002	42.1621627807617
2003	44.3243255615234
2004	40.2985076904297
2005	44.6078414916992
2006	48.0392150878906
2007	45.1456298828125
2008	41.262134552002
2009	32.0574150085449
2010	30.1435413360596
2011	32.7014236450195
2012	30.8056869506836
2013	27.962085723877
2014	26.9230766296387
2015	24.2857151031494
2016	25.238094329834
2017	25.7142848968506
2018	22.8571434020996
2019	20.4761905670166
2020	20.9523811340332
2021	20.9523811340332
2022	20.7547168731689