Year	Number
2006	12.269432830003788
2007	13.07883594957584
2008	10.304935728509347
2009	11.175262623218448
2010	11.471234622169552
2011	12.733068348086196
2012	10.196028828414837
2013	10.941241363985855
2014	11.950926169723688
2015	15.26402253205588
2016	31.192560514604644
2017	24.62574828085436
2018	21.217723178517613
2019	19.065038620063447
2020	20.506254932641486
2021	17.735254380636583
2022	17.232043378459135
2023	12.474676128852026