Year	%
1990	29.0306867998052
1991	28.9492242595204
1992	28.8775783552103
1993	28.806410797132
1994	28.7777204744714
1995	28.7778098815371
1996	28.8078646092583
1997	28.8621444201313
1998	28.9267528397963
1999	29.0167438546491
2000	29.1231818555346
2001	29.2392722806479
2002	29.3619178677482
2003	29.4745540940707
2004	29.5693277310924
2005	29.6730142821348
2006	29.848957084632
2007	29.9429874572406
2008	30.07309622518
2009	30.2297524129249
2010	30.3944903023244
2011	30.5908934623508
2012	30.8695860712744
2013	31.248821866164
2014	31.6620974861763
2015	32.1121185621577
2016	32.542729183804
2017	32.9914763662884
2018	33.4535494179411
2019	33.7336194694306
2020	33.8108622721915
2021	33.8316746971676
2022	33.7918099406064