Year	Percent
1990	32.903
1991	33.8
1992	33.145
1993	34.053
1994	35.089
1995	36.122
1996	34.565
1997	37.663
1998	40.12
1999	40.173
2000	38.596
2001	41.829
2002	42.228
2003	41.628
2004	41.001
2005	44.695
2006	44.589
2007	45.71
2008	46.048
2009	46.343
2010	44.145
2011	46.188
2012	45.927
2013	46.467
2014	49.336
2015	48.804
2016	45.023
2017	45.325
2018	45.617
2019	45.882
2020	46.107
2021	46.315
2022	46.483
2023	46.619
2024	46.736
2025	46.842
2026	46.963
2027	47.077
2028	47.184
2029	47.284
2030	47.376