Year	Percent
1990	44.164
1991	44.42
1992	45.954
1993	46.387
1994	47.289
1995	48.329
1996	55.49
1997	55.112
1998	54.915
1999	55.431
2000	55.913
2001	57.045
2002	56.221
2003	54.227
2004	55.482
2005	57.278
2006	59.083
2007	62.622
2008	63.92
2009	65.244
2010	65.306
2011	66.183
2012	65.51
2013	66.21
2014	66.59
2015	66.597
2016	66.122
2017	66.082
2018	65.97
2019	65.766
2020	65.463
2021	65.022
2022	64.489
2023	63.882
2024	63.224
2025	62.53
2026	61.771
2027	60.983
2028	60.196
2029	59.436
2030	58.725