Year	Number
1996	19.1489353179932
1998	12.7659578323364
2000	17.4603176116943
2002	15.8730154037476
2003	9.04522609710693
2004	13.1067962646484
2005	17.4757289886475
2006	16.9082126617432
2007	13.5265703201294
2008	13.942307472229
2009	10.4265403747559
2010	11.3744077682495
2011	10.9004735946655
2012	10.9004735946655
2013	12.3222751617432
2014	13.8095235824585
2015	17.1428565979004
2016	14.7619047164917
2017	18.5714282989502
2018	13.6792449951172
2019	19.3396224975586
2020	18.3962268829346
2021	22.6415100097656
2022	24.5283012390137