Year	Percent
1990	73.82
1991	73.632
1992	73.473
1993	73.176
1994	72.835
1995	72.641
1996	72.478
1997	72.991
1998	72.953
1999	73.369
2000	73.728
2001	74.178
2002	74.648
2003	75.064
2004	75.096
2005	75.146
2006	75.199
2007	75.209
2008	74.484
2009	73.764
2010	73.448
2011	73.731
2012	74.177
2013	74.808
2014	75.274
2015	75.639
2016	76.064
2017	76.24
2018	76.423
2019	76.616
2020	76.817
2021	77.096
2022	77.387
2023	77.673
2024	77.925
2025	78.127
2026	78.224
2027	78.257
2028	78.239
2029	78.194
2030	78.138