Year	Percent
1990	0
1996	0.00585
1997	0.01427
1998	0.02788
1999	0.04089
2000	0.05339
2001	0.07854
2002	0.12854
2003	0.15156
2004	0.2234
2005	0.2682
2006	0.31116
2007	0.37582
2008	1
2009	1.8
2010	2
2011	2.2
2012	3
2013	3.4
2014	3.6
2015	3.8
2016	4