Year	Percent
1990	39.27
1991	39.43
1992	40.62
1993	40.55
1994	41.15
1995	40.93
1996	40.92
1997	42.01
1998	40.35
1999	40.69
2000	40.69
2001	41.27
2002	42.76
2003	39.84
2004	41.35
2005	41.23
2006	41.96
2007	42.85
2008	41.84
2009	41.45
2010	40.6
2011	40.56
2012	41.64
2013	42.57
2014	43.03
2015	42.18
2016	42.15
2017	42.207
2018	42.265
2019	42.322
2020	42.38
2021	42.437
2022	42.495
2023	42.552
2024	42.61
2025	42.667
2026	42.724
2027	42.782
2028	42.839
2029	42.897
2030	42.954