Year	Percent
1990	70.709
1991	70.495
1992	70.337
1993	69.878
1994	69.839
1995	69.706
1996	69.425
1997	69.268
1998	69.185
1999	69.033
2000	68.898
2001	68.796
2002	68.721
2003	68.79
2004	69.145
2005	69.391
2006	69.297
2007	69.329
2008	69.437
2009	69.619
2010	69.965
2011	70.034
2012	70.283
2013	70.539
2014	70.856
2015	71.147
2016	71.226
2017	71.346
2018	71.468
2019	71.59
2020	71.714
2021	71.841
2022	71.97
2023	72.099
2024	72.229
2025	72.359
2026	72.492
2027	72.625
2028	72.759
2029	72.894
2030	73.029