Year	Percent
1992	1.68943
1993	2.22112
1994	2.67879
1995	2.55887
1996	2.73115
1997	3.18518
1998	3.22742
1999	2.83985
2000	2.5293
2001	2.45901
2002	2.62433
2003	3.22138
2004	3.47502
2005	3.84388
2006	3.66557
2007	3.05506
2008	2.5387
2009	2.43136
2010	2.20852
2011	1.84319
2012	1.63396
2013	1.60705
2014	1.51707
2015	1.40654
2016	1.19827
2017	1.12589