Year	Percent
1990	46.403
1991	47.375
1992	48.856
1993	50.758
1994	51.173
1995	50.405
1996	51.033
1997	50.172
1998	49.303
1999	49.197
2000	48.49
2001	48.114
2002	47.734
2003	47.685
2004	47.717
2005	48.243
2006	48.222
2007	48.851
2008	49.404
2009	49.895
2010	50.571
2011	51.584
2012	52.277
2013	52.67
2014	53.388
2015	53.891
2016	53.939
2017	54.116
2018	54.294
2019	54.471
2020	54.649
2021	54.826
2022	55.004
2023	55.181
2024	55.359
2025	55.536
2026	55.714
2027	55.891
2028	56.069
2029	56.246
2030	56.423