Year	Percent
1990	47.828
1991	48.053
1992	48.224
1993	48.304
1994	48.276
1995	48.236
1996	48.153
1997	48.101
1998	48.295
1999	48.32
2000	48.281
2001	48.308
2002	48.297
2003	48.228
2004	48.095
2005	48.973
2006	49.483
2007	49.582
2008	49.1
2009	49.941
2010	50.156
2011	51.009
2012	50.644
2013	50.616
2014	51.471
2015	51.216
2016	51.185
2017	51.439
2018	51.693
2019	51.937
2020	52.166
2021	52.382
2022	52.584
2023	52.777
2024	52.969
2025	53.163
2026	53.36
2027	53.56
2028	53.763
2029	53.968
2030	54.175