Year	Percent
1990	36.558
1991	37.947
1992	38.738
1993	39.447
1994	40.054
1995	40.477
1996	40.53
1997	40.966
1998	41.532
1999	43.141
2000	43.57
2001	41.723
2002	42.357
2003	42.679
2004	43.957
2005	45.487
2006	45.622
2007	46.409
2008	46.731
2009	46.747
2010	47.491
2011	46.806
2012	46.89
2013	47.595
2014	48.01
2015	48.024
2016	47.766
2017	47.808
2018	47.839
2019	47.851
2020	47.834
2021	47.771
2022	47.687
2023	47.588
2024	47.487
2025	47.393
2026	47.312
2027	47.247
2028	47.197
2029	47.157
2030	47.122