Year	Percent
1990	47.003
1991	46.982
1992	46.897
1993	46.871
1994	47.671
1995	48.317
1996	48.979
1997	49.98
1998	47.268
1999	47.782
2000	48.83
2001	49.294
2002	49.809
2003	49.067
2004	50.089
2005	50.395
2006	50.598
2007	50.519
2008	50.186
2009	49.235
2010	49.498
2011	49.703
2012	50.024
2013	50.295
2014	51.436
2015	51.914
2016	52.234
2017	52.211
2018	52.179
2019	52.104
2020	51.964
2021	51.784
2022	51.548
2023	51.268
2024	50.961
2025	50.634
2026	50.306
2027	49.955
2028	49.587
2029	49.211
2030	48.836