Year	Percent
1990	61.266
1991	60.652
1992	61.393
1993	62.258
1994	62.999
1995	63.794
1996	64.49
1997	63.563
1998	63.459
1999	63.327
2000	63.189
2001	63.275
2002	63.371
2003	63.475
2004	64.189
2005	64.2
2006	64.117
2007	63.989
2008	63.817
2009	63.607
2010	63.492
2011	63.288
2012	62.061
2013	63.231
2014	61.856
2015	61.86
2016	62.568
2017	62.247
2018	61.891
2019	61.511
2020	61.111
2021	60.749
2022	60.379
2023	59.997
2024	59.605
2025	59.204
2026	58.867
2027	58.534
2028	58.207
2029	57.891
2030	57.592