Year	Percent
1990	39.706
1991	40.207
1992	40.981
1993	42.955
1994	44.479
1995	43.111
1996	41.756
1997	41.95
1998	45.306
1999	45.675
2000	45.434
2001	45.187
2002	44.948
2003	46.439
2004	44.799
2005	45.506
2006	46.214
2007	46.513
2008	46.581
2009	46.61
2010	46.398
2011	46.727
2012	47.066
2013	48.205
2014	47.664
2015	47.146
2016	46.669
2017	46.968
2018	47.284
2019	47.595
2020	47.888
2021	48.182
2022	48.462
2023	48.725
2024	48.972
2025	49.201
2026	49.427
2027	49.636
2028	49.827
2029	50.001
2030	50.157