Year	Percent
1990	77.629
1991	75.386
1992	76.301
1993	76.68
1994	76.924
1995	77.514
1996	75.116
1997	76.024
1998	75.756
1999	75.448
2000	75.125
2001	75.106
2002	75.105
2003	75.108
2004	75.663
2005	75.44
2006	75.11
2007	74.744
2008	74.334
2009	73.881
2010	73.052
2011	72.974
2012	71.964
2013	72.019
2014	69.049
2015	69.941
2016	70.496
2017	70.033
2018	69.549
2019	69.05
2020	68.541
2021	68.074
2022	67.611
2023	67.149
2024	66.687
2025	66.225
2026	65.823
2027	65.433
2028	65.053
2029	64.686
2030	64.335