Year	Percent
1990	76.938
1991	76.923
1992	77.186
1993	78.06
1994	77.917
1995	76.973
1996	76.264
1997	75.999
1998	76.006
1999	75.837
2000	74.248
2001	74.299
2002	73.503
2003	72.912
2004	73.471
2005	73.01
2006	73.445
2007	74.197
2008	74.277
2009	73.263
2010	74.971
2011	75.474
2012	75.101
2013	74.857
2014	74.689
2015	74.843
2016	74.332
2017	74.419
2018	74.491
2019	74.548
2020	74.587
2021	74.591
2022	74.578
2023	74.555
2024	74.527
2025	74.499
2026	74.459
2027	74.421
2028	74.383
2029	74.339
2030	74.286