Year	Percent
1990	50.531
1991	53.389
1992	56.231
1993	56.253
1994	56.286
1995	56.33
1996	56.382
1997	56.447
1998	57.378
1999	58.298
2000	57.851
2001	57.403
2002	56.957
2003	56.51
2004	56.064
2005	55.62
2006	56.509
2007	57.392
2008	58.264
2009	58.306
2010	59.247
2011	58.946
2012	58.648
2013	58.354
2014	58.388
2015	56.169
2016	58.396
2017	58.49
2018	58.584
2019	58.677
2020	58.769
2021	58.858
2022	58.948
2023	59.037
2024	59.123
2025	59.207
2026	59.286
2027	59.363
2028	59.438
2029	59.513
2030	59.588