Year	Number
1996	21.1055278778076
1998	26
2000	26.3681583404541
2002	25.8706474304199
2003	29.3532333374023
2004	21.634614944458
2005	31.1004791259766
2006	25.3588523864746
2007	26.7942581176758
2008	34.6153831481934
2009	29.8578205108643
2010	28.9099521636963
2011	30.5164318084717
2012	31.9248828887939
2013	34.7417831420898
2014	29.3269233703613
2015	28.0952377319336
2016	35.7142868041992
2017	32.8571434020996
2018	35.238094329834
2019	36.6666679382324
2020	40
2021	39.0476188659668
2022	37.7358474731445