Year	Percent
1990	36.068
1991	35.354
1992	34.503
1993	28.618
1994	33.055
1995	33.12
1996	32.113
1997	30.239
1998	30.95
1999	31.165
2000	28.856
2001	29.57
2002	30.583
2003	29.666
2004	26.68
2005	27.248
2006	27.429
2007	27.587
2008	28.798
2009	31.024
2010	33.455
2011	35.27
2012	36.743
2013	38.393
2014	38.836
2015	40.282
2016	41.995
2017	42.102
2018	42.206
2019	42.309
2020	42.411
2021	42.516
2022	42.618
2023	42.719
2024	42.821
2025	42.923
2026	43.027
2027	43.133
2028	43.24
2029	43.35
2030	43.463