Year	Percent
1990	59.31
1991	58.77
1992	61.82
1993	58.72
1994	57.6
1995	58.52
1996	57.25
1997	57.35
1998	58.05
1999	54.47
2000	55.73
2001	55.96
2002	55.24
2003	55.31
2004	50.5
2005	50.819
2006	49.475
2007	49.824
2008	48.937
2009	48.254
2010	48.324
2011	47.114
2012	46.145
2013	46.035
2014	46.136
2015	46.321
2016	47.42
2017	47.063
2018	46.707
2019	46.35
2020	45.993
2021	45.637
2022	45.28
2023	44.924
2024	44.567
2025	44.21
2026	43.854
2027	43.497
2028	43.14
2029	42.784
2030	42.427