Year	Percent
1991	5.241
1992	5.319
1993	5.789
1994	5.585
1995	5.811
1996	8.181
1997	6.625
1998	6.627
1999	6.226
2000	8.234
2001	11.299
2002	12.153
2003	11.155
2004	11.121
2005	11.563
2006	11.742
2007	11.764
2008	12.354
2009	12.83
2010	10.47
2011	10.216
2012	10.485
2013	10.578
2014	10.599
2015	10.07
2016	9.865
2017	9.275
2018	9.213
2019	9.157
2020	9.247
2021	9.328
2022	9.349