Year	Number
1996	33.5
1998	29.3532333374023
2000	24.8756217956543
2002	25.8706474304199
2003	26.3681583404541
2004	17.7884616851807
2005	22.5961532592773
2006	25.480770111084
2007	29.3269233703613
2008	21.634614944458
2009	21.8009471893311
2010	22.748815536499
2011	21.5962448120117
2012	21.5962448120117
2013	21.1267604827881
2014	22.1674880981445
2015	23.645320892334
2016	24.630542755127
2017	24.1379318237305
2018	23.7864074707031
2019	24.6376819610596
2020	25.1207733154297
2021	28.5024147033691
2022	28.5024147033691