Year	Percent
1973-01-01	2.8555000000000000
1974-01-01	3.2593600000000000
1975-01-01	4.1152600000000000
1976-01-01	4.1944900000000000
1977-01-01	4.0096400000000000
1978-01-01	4.6836400000000005
1979-01-01	5.4844300000000010
1980-01-01	5.8680600000000000
1981-01-01	6.4978200000000000
1982-01-01	9.0750800000000000
1983-01-01	12.4278000000000000
1984-01-01	14.3142000000000000
1985-01-01	16.5978000000000000
1986-01-01	19.4390000000000000
1987-01-01	19.3971000000000000
1988-01-01	21.7447000000000000
1989-01-01	23.7585000000000000
1990-01-01	19.6428000000000000
1991-01-01	20.1513000000000000
1992-01-01	25.5090000000000000
1993-01-01	32.0034000000000000
1994-01-01	35.3977000000000000
1995-01-01	36.9602000000000000
1996-01-01	34.1332000000000000
1997-01-01	35.7467000000000000
1998-01-01	46.7251000000000000
1999-01-01	45.4515000000000000
2000-01-01	40.3893000000000000
2001-01-01	44.6964000000000000
2002-01-01	46.5942000000000000
2003-01-01	46.0528000000000000
2004-01-01	46.0616000000000000
2005-01-01	43.8791000000000000
2006-01-01	43.4373000000000000
2007-01-01	44.2817000000000000
2008-01-01	44.8941000000000000
2009-01-01	58.7644000000000000
2010-01-01	48.3635000000000000
2011-01-01	41.2916000000000000
2012-01-01	41.3277000000000000
2013-01-01	46.7035000000000000
2014-01-01	52.4954000000000000
2015-01-01	65.4322000000000000
2016-01-01	69.0316000000000000