Year	Percent
1991	10.955
1992	10.938
1993	10.613
1994	10.487
1995	10.846
1996	11.107
1997	11.576
1998	10.271
1999	10.778
2000	11.655
2001	11.971
2002	11.312
2003	11.283
2004	11.56
2005	11.584
2006	11.859
2007	12.008
2008	11.759
2009	12.152
2010	12.216
2011	12.484
2012	11.935
2013	12.388
2014	12.685
2015	12.422
2016	12.54
2017	12.779
2018	12.98
2019	13.131
2020	13.307
2021	13.458
2022	13.607
