Year	Percent
1990	68.389
1991	68.54
1992	67.968
1993	67.841
1994	67.765
1995	67.792
1996	67.813
1997	68.234
1998	69.038
1999	69.749
2000	70.362
2001	70.725
2002	72.094
2003	73.258
2004	73.403
2005	72.983
2006	73.335
2007	74.181
2008	74.189
2009	74.239
2010	74.283
2011	74.105
2012	74.251
2013	74.59
2014	74.156
2015	74.104
2016	74.378
2017	74.579
2018	74.777
2019	74.971
2020	75.161
2021	75.334
2022	75.493
2023	75.656
2024	75.844
2025	76.073
2026	76.328
2027	76.621
2028	76.937
2029	77.249
2030	77.542