Year	Percent
1990	40.143
1991	40.498
1992	40.997
1993	40.999
1994	40.954
1995	40.875
1996	40.417
1997	40.829
1998	40.897
1999	40.801
2000	40.868
2001	42.005
2002	43.16
2003	43.921
2004	44.88
2005	45.108
2006	47.062
2007	48.564
2008	48.645
2009	48.836
2010	51.133
2011	52.616
2012	54.071
2013	55.676
2014	57.342
2015	58.934
2016	58.373
2017	58.087
2018	57.841
2019	57.673
2020	57.574
2021	57.084
2022	56.737
2023	56.546
2024	56.493
2025	56.53
2026	56.283
2027	56.067
2028	55.895
2029	55.776
2030	55.703