Year	Percent
1992	6.036
1993	6.301
1994	6.425
1995	4.894
1996	5.194
1997	5.0228
1998	5.2889
1999	5.5631
2000	10.6223
2001	7.4972
2002	7.6532
2003	10.2951
2004	8.7084
2005	8.4429
2006	6.1621
2007	5.7373
2008	4.3847
2009	5.5185
2010	6.5039
2011	6.2096
2012	6.6319
2013	6.916
2014	6.3506
2015	4.8172
2016	3.5119
2017	3.0826