Year	Number
1996	16.5
1998	12.4378108978271
2000	14.9253730773926
2002	15.9203977584839
2003	16.4179096221924
2004	21.634614944458
2005	13.4615383148193
2006	8.65384578704834
2007	10.0961542129517
2008	12.5
2009	11.3744077682495
2010	13.2701425552368
2011	12.6760559082031
2012	14.5539903640747
2013	13.6150236129761
2014	10.837438583374
2015	12.8078813552856
2016	12.8078813552856
2017	12.8078813552856
2018	13.1067962646484
2019	12.0772943496704
2020	11.5942029953003
2021	11.1111106872559
2022	11.1111106872559