Year	Percent
1990	46.307
1991	46.576
1992	47.482
1993	47.633
1994	47.831
1995	47.965
1996	47.779
1997	48.982
1998	49.345
1999	49.254
2000	49.366
2001	50.485
2002	51.713
2003	52.389
2004	53.568
2005	53.568
2006	56.201
2007	57.798
2008	57.206
2009	56.622
2010	58.943
2011	61.201
2012	62.622
2013	64.002
2014	65.317
2015	66.545
2016	66.248
2017	66.321
2018	66.427
2019	66.565
2020	66.724
2021	66.785
2022	66.893
2023	67.055
2024	67.259
2025	67.486
2026	67.475
2027	67.47
2028	67.474
2029	67.488
2030	67.507