Year	Number
1996	40.8602142333984
1998	43.3155097961426
2000	37.2340431213379
2002	38.624340057373
2003	32.8042335510254
2004	30.5418720245361
2005	37.073169708252
2006	32.1951217651367
2007	36.8932037353516
2008	37.8640785217285
2009	40.6698570251465
2010	40.9523811340332
2011	38.3886260986328
2012	34.5971565246582
2013	34.1232223510742
2014	29.3269233703613
2015	24.761905670166
2016	17.1428565979004
2017	19.0476188659668
2018	23.8095245361328
2019	22.380952835083
2020	24.761905670166
2021	22.8571434020996
2022	21.698112487793