Year	Percent
1990	78.167
1991	77.556
1992	77.027
1993	76.501
1994	75.888
1995	75.149
1996	74.467
1997	73.658
1998	72.96
1999	71.04
2000	68.957
2001	69.377
2002	69.87
2003	70.41
2004	70.957
2005	71.486
2006	72.018
2007	71.455
2008	70.904
2009	70.373
2010	67.278
2011	71.96
2012	75.524
2013	78.269
2014	78.211
2015	78.249
2016	78.236
2017	78.422
2018	78.586
2019	78.722
2020	78.827
2021	78.885
2022	78.921
2023	78.931
2024	78.914
2025	78.868
2026	78.777
2027	78.662
2028	78.541
2029	78.436
2030	78.358