Year	Percent
1990	50.939
1991	51.662
1992	52.477
1993	53.03
1994	53.338
1995	53.455
1996	53.687
1997	53.854
1998	54.047
1999	54.224
2000	54.429
2001	54.42
2002	54.282
2003	54.052
2004	53.765
2005	53.698
2006	53.666
2007	53.687
2008	53.821
2009	53.663
2010	53.134
2011	53.888
2012	53.784
2013	53.709
2014	53.954
2015	53.735
2016	52.662
2017	52.731
2018	52.716
2019	52.61
2020	52.411
2021	52.137
2022	51.79
2023	51.368
2024	50.873
2025	50.309
2026	49.698
2027	49.035
2028	48.366
2029	47.76
2030	47.253