Year	Percent
1980-01-01	2.3343900000000000
1981-01-01	2.9982599999999997
1982-01-01	3.0900400000000000
1983-01-01	3.4659100000000000
1984-01-01	3.8895100000000000
1985-01-01	4.1071800000000005
1986-01-01	4.3897600000000000
1987-01-01	5.6799000000000000
1988-01-01	6.2559300000000000
1989-01-01	6.0789100000000000
1990-01-01	6.3945800000000000
1991-01-01	6.4762699999999995
1992-01-01	6.1310199999999995
1993-01-01	8.7603000000000000
1994-01-01	8.5320800000000000
1995-01-01	6.1364600000000000
1996-01-01	9.2009200000000000
1997-01-01	10.1294000000000000
1998-01-01	9.6470700000000000
1999-01-01	10.3322000000000000
2000-01-01	8.7269000000000000
2001-01-01	13.5116000000000000
2002-01-01	13.0808000000000000
2003-01-01	14.8884000000000000
2004-01-01	13.3681000000000000
2005-01-01	27.8297000000000000
2006-01-01	25.9000000000000000
2007-01-01	25.5374000000000000
2008-01-01	19.1727000000000000
2009-01-01	24.5053000000000000
2010-01-01	23.2545000000000000
2011-01-01	26.6687000000000000
2012-01-01	33.5562000000000000
2013-01-01	29.7732000000000000
2014-01-01	25.7244000000000000
2015-01-01	19.1748000000000000
2016-01-01	17.9390000000000000