Year	Percent
1990	79.112
1991	79.075
1992	79.083
1993	79.196
1994	78.864
1995	78.937
1996	78.836
1997	78.584
1998	78.374
1999	78.432
2000	78.224
2001	78.597
2002	79.11
2003	79.11
2004	79.13
2005	79.063
2006	78.845
2007	78.889
2008	78.954
2009	79.221
2010	79.52
2011	79.575
2012	79.532
2013	79.471
2014	79.448
2015	79.656
2016	79.568
2017	79.594
2018	79.671
2019	79.746
2020	79.764
2021	79.661
2022	79.525
2023	79.4
2024	79.323
2025	79.292
2026	79.231
2027	79.221
2028	79.261
2029	79.321
2030	79.369