Year	Percent
1990	30.056
1991	29.768
1992	29.538
1993	29.184
1994	29.633
1995	29.903
1996	29.961
1997	30.142
1998	30.59
1999	30.497
2000	30.779
2001	30.998
2002	31.335
2003	31.397
2004	31.602
2005	31.872
2006	32.107
2007	32.53
2008	32.627
2009	32.21
2010	32.321
2011	32.594
2012	32.791
2013	32.934
2014	33.14
2015	33.426
2016	33.55
2017	33.675
2018	33.799
2019	33.924
2020	34.048
2021	34.173
2022	34.297
2023	34.422
2024	34.546
2025	34.67
2026	34.795
2027	34.919
2028	35.044
2029	35.168
2030	35.293