Year	Percent
1990	44.191
1991	44.479
1992	44.787
1993	45.16
1994	45.58
1995	46.022
1996	46.364
1997	46.696
1998	47.023
1999	47.392
2000	47.803
2001	48.083
2002	48.391
2003	48.706
2004	48.988
2005	49.283
2006	49.571
2007	49.869
2008	51.631
2009	49.946
2010	48.284
2011	48.908
2012	49.257
2013	50.268
2014	50.546
2015	51.906
2016	52.058
2017	52.242
2018	52.423
2019	52.596
2020	52.757
2021	52.901
2022	53.033
2023	53.152
2024	53.256
2025	53.346
2026	53.42
2027	53.478
2028	53.527
2029	53.58
2030	53.645