Year	Percent
1973-01-01	2.7711400000000000
1974-01-01	3.8845600000000000
1975-01-01	5.8971300000000010
1976-01-01	5.5560800000000010
1977-01-01	7.3136700000000000
1978-01-01	6.8790400000000000
1979-01-01	5.7114900000000000
1980-01-01	5.0275300000000005
1981-01-01	4.9238000000000000
1982-01-01	4.9396600000000000
1983-01-01	3.4341600000000000
1984-01-01	2.9382700000000000
1985-01-01	2.8472700000000000
1986-01-01	3.2476900000000000
1987-01-01	3.3080500000000000
1988-01-01	2.1882000000000000
1989-01-01	1.9738000000000000
1990-01-01	2.2983300000000000
1991-01-01	1.0561500000000000
1992-01-01	0.9136629999999999
1993-01-01	0.9045840000000000
1994-01-01	0.9086530000000000
1995-01-01	2.8040700000000003
1996-01-01	3.0259000000000000
1997-01-01	7.1506600000000000
1998-01-01	17.1266000000000000
1999-01-01	13.3734000000000000
2000-01-01	8.2070800000000000
2001-01-01	8.1141700000000000
2002-01-01	6.2676200000000000
2003-01-01	5.2029400000000000
2004-01-01	5.9331100000000000
2005-01-01	7.0445199999999994
2006-01-01	5.5053600000000000
2007-01-01	1.8481500000000000
2008-01-01	2.5248800000000000
2009-01-01	3.0898700000000000
2010-01-01	4.7030100000000000
2011-01-01	5.1424699999999990
2012-01-01	3.8008599999999997
2013-01-01	4.6323800000000000