Year	Percent
1990	50.379
1991	50.659
1992	51.378
1993	52.306
1994	53.09
1995	53.581
1996	54.113
1997	54.301
1998	54.342
1999	54.44
2000	54.65
2001	54.755
2002	55.051
2003	55.468
2004	55.738
2005	55.911
2006	56.059
2007	56.075
2008	56.128
2009	56.099
2010	56.158
2011	56.371
2012	56.527
2013	56.725
2014	57.012
2015	57.36
2016	57.751
2017	57.835
2018	57.91
2019	57.985
2020	58.064
2021	58.148
2022	58.237
2023	58.324
2024	58.395
2025	58.447
2026	58.487
2027	58.511
2028	58.537
2029	58.587
2030	58.672