Year	Number
1996	8
1998	5.47263669967651
2000	8.95522403717041
2002	10.945273399353
2003	9.95024871826172
2004	18.75
2005	21.634614944458
2006	17.7884616851807
2007	14.9038457870483
2008	14.9038457870483
2009	13.2701425552368
2010	13.2701425552368
2011	13.6150236129761
2012	15.4929580688477
2013	15.962441444397
2014	21.1822662353516
2015	20.6896553039551
2016	19.2118225097656
2017	16.7487678527832
2018	13.5922327041626
2019	14.0096616744995
2020	13.5265703201294
2021	14.9758453369141
2022	15.4589376449585