Year	Percent
1987-01-01	5.17488127323857
1988-01-01	9.34212688547206
1989-01-01	6.46256171146444
1990-01-01	8.19137132040971
1991-01-01	6.96568127760758
1992-01-01	7.52351717022744
1993-01-01	5.73690583357398
1994-01-01	7.65824302019538
1995-01-01	5.81818181818193
1996-01-01	7.31348259330352
1997-01-01	5.60802843389853
1998-01-01	8.61483153647288
1999-01-01	4.29072851723815
2000-01-01	2.15851810619413
2001-01-01	4.27267024465103
2002-01-01	3.22508361481579
2003-01-01	3.69631886537926
2004-01-01	4.22949770219265
2005-01-01	5.44481213092114
2006-01-01	4.86632048837462
2007-01-01	4.81676531343752
2008-01-01	10.22666454731480
2009-01-01	4.21903052064627
2010-01-01	3.68001483129403
2011-01-01	5.35604778982150
2012-01-01	3.02696391124798
2013-01-01	2.91629018356998
2014-01-01	3.14299050879107
2015-01-01	1.22127006080706
2016-01-01	2.00000000000002
2017-01-01	2.87205620900761