Year	Number
1996	25.6830596923828
1998	22.4043712615967
2000	19.1256828308105
2002	16.2162170410156
2003	14.0540542602539
2004	10.4477615356445
2005	12.2549018859863
2006	9.26829242706299
2007	12.1359224319458
2008	12.62135887146
2009	12.4401912689209
2010	8.61244010925293
2011	12.3222751617432
2012	13.2701425552368
2013	13.2701425552368
2014	10.5769233703613
2015	11.9047622680664
2016	11.9047622680664
2017	10.4761905670166
2018	11.9047622680664
2019	12.380952835083
2020	11.9047622680664
2021	11.4285717010498
2022	10.8490562438965