Year	Percent
1990	80.247
1991	80.252
1992	80.159
1993	80.079
1994	79.969
1995	79.83
1996	79.702
1997	79.608
1998	79.591
1999	79.591
2000	79.487
2001	79.395
2002	79.279
2003	79.125
2004	78.934
2005	78.731
2006	78.548
2007	78.345
2008	78.202
2009	78.105
2010	78.276
2011	78.53
2012	78.871
2013	79.274
2014	79.653
2015	79.068
2016	79.083
2017	79.283
2018	79.434
2019	79.548
2020	79.632
2021	79.689
2022	79.707
2023	79.695
2024	79.664
2025	79.627
2026	79.589
2027	79.548
2028	79.508
2029	79.476
2030	79.455