Year	Percent
1991	12.585
1992	12.722
1993	13.03
1994	13.105
1995	13.266
1996	13.274
1997	13.352
1998	13.574
1999	13.928
2000	14.122
2001	13.912
2002	14.346
2003	14.563
2004	14.931
2005	15.476
2006	15.918
2007	16.217
2008	16.71
2009	17.063
2010	17.574
2011	19.52
2012	21.339
2013	22.225
2014	23.135
2015	24.26
2016	25.384
2017	25.943
2018	26.952
2019	27.919
2020	28.92
2021	29.879
2022	30.64