Year	Percent
1991	5.555
1992	6.098
1993	6.831
1994	6.708
1995	7.061
1996	6.912
1997	6.88
1998	7.391
1999	8.043
2000	7.832
2001	9.766
2002	10.04
2003	8.295
2004	7.708
2005	7.061
2006	6.542
2007	6.411
2008	6.806
2009	6.778
2010	6.295
2011	16.302
2012	4.289
2013	11.138
2014	16.064
2015	14.599
2016	13.874
2017	9.277
2018	8.167
2019	7.675
2020	6.717
2021	6.24
2022	5.982