Year	Percent
1990	45.609
1991	45.783
1992	47.53
1993	46.945
1994	48.198
1995	49.284
1996	49.766
1997	50.283
1998	50.818
1999	51.259
2000	51.682
2001	53.165
2002	52.726
2003	52.305
2004	52.441
2005	52.541
2006	53.219
2007	53.67
2008	54.292
2009	54.901
2010	55.335
2011	55.977
2012	55.789
2013	54.974
2014	55.963
2015	55.725
2016	55.928
2017	56.12
2018	56.306
2019	56.476
2020	56.622
2021	56.771
2022	56.909
2023	57.033
2024	57.147
2025	57.249
2026	57.372
2027	57.495
2028	57.613
2029	57.721
2030	57.813