Year	Percent
1990	20.509
1991	21.973
1992	23.53
1993	25.172
1994	26.872
1995	28.609
1996	30.434
1997	32.273
1998	34.138
1999	36.061
2000	38.064
2001	40.631
2002	43.313
2003	46.093
2004	48.945
2005	51.841
2006	54.72
2007	54.071
2008	53.434
2009	52.787
2010	52.115
2011	51.406
2012	50.669
2013	49.895
2014	49.078
2015	46.484
2016	44.313
2017	44.89
2018	45.437
2019	45.959
2020	46.464
2021	46.94
2022	47.4
2023	47.848
2024	48.285
2025	48.714
2026	49.129
2027	49.536
2028	49.941
2029	50.348
2030	50.759