Year	Percent
1990	45.293
1991	48.609
1992	51.944
1993	55.271
1994	58.566
1995	58.601
1996	58.591
1997	58.58
1998	58.574
1999	58.583
2000	58.611
2001	58.6
2002	58.623
2003	58.663
2004	58.704
2005	58.762
2006	58.745
2007	58.713
2008	58.713
2009	58.726
2010	58.762
2011	58.833
2012	58.891
2013	58.925
2014	58.987
2015	59.055
2016	59.104
2017	59.128
2018	59.143
2019	59.141
2020	59.12
2021	59.076
2022	59.015
2023	58.945
2024	58.877
2025	58.817
2026	58.761
2027	58.715
2028	58.677
2029	58.647
2030	58.622