Year	Percent
1990	2.3
1997	0.5
1999	0.3
2000	0.2
2001	0.5
2002	0.4
2004	0.9
2005	0.5
2006	0.6
2007	0.8
2008	0.9
2009	0.8
2011	1.1
2012	0.9
2013	1
2014	1.1
2015	1.1
2016	1.1