Year	Percent
1990	72.254
1991	72.382
1992	72.537
1993	72.741
1994	72.967
1995	73.093
1996	73.064
1997	72.947
1998	72.865
1999	72.761
2000	72.631
2001	72.545
2002	72.582
2003	72.566
2004	72.054
2005	72.498
2006	72.839
2007	73.142
2008	73.454
2009	72.727
2010	72.884
2011	72.994
2012	73.166
2013	73.343
2014	73.411
2015	73.248
2016	73.429
2017	73.684
2018	73.862
2019	73.903
2020	73.767
2021	73.467
2022	72.98
2023	72.381
2024	71.793
2025	71.296
2026	70.894
2027	70.582
2028	70.364
2029	70.231
2030	70.179