Year	Percent
1990	67.153
1991	68.867
1992	67.972
1993	68.979
1994	68.308
1995	67.613
1996	69.2
1997	69.872
1998	70.305
1999	68.223
2000	66.878
2001	66.948
2002	66.987
2003	66.77
2004	67.017
2005	66.963
2006	66.178
2007	65.377
2008	64.328
2009	63.551
2010	62.761
2011	62.107
2012	61.451
2013	60.77
2014	60.051
2015	59.304
2016	59.432
2017	59.412
2018	59.375
2019	59.318
2020	59.251
2021	59.253
2022	59.245
2023	59.219
2024	59.18
2025	59.14
2026	59.167
2027	59.197
2028	59.208
2029	59.184
2030	59.12
