Year	Percent
1975-01-01	5.1714800000000000
1976-01-01	5.3293900000000000
1977-01-01	7.5056199999999995
1978-01-01	4.7415900000000000
1979-01-01	19.2200000000000000
1980-01-01	14.9709000000000000
1981-01-01	25.9445000000000000
1982-01-01	28.2396000000000000
1983-01-01	43.5913000000000000
1984-01-01	31.4285000000000000
1985-01-01	34.8343000000000000
1986-01-01	31.1998000000000000
1987-01-01	27.5763000000000000
1988-01-01	21.6021000000000000
1989-01-01	16.7914000000000000
1990-01-01	13.6745000000000000
1991-01-01	21.4792000000000000
1992-01-01	31.8214000000000000
1993-01-01	50.5713000000000000
1994-01-01	79.9026000000000000
1995-01-01	65.5545000000000000
1996-01-01	61.4131000000000000
1997-01-01	64.1947000000000000
1998-01-01	75.1932000000000000
1999-01-01	66.9886000000000000
2000-01-01	114.1750000000000000
2001-01-01	112.9940000000000000
2002-01-01	85.9657000000000000
2003-01-01	78.2083000000000000
2004-01-01	118.4930000000000000
2005-01-01	119.9079999999999900
2006-01-01	137.9820000000000000
2007-01-01	156.8710000000000000
2008-01-01	144.0930000000000000
2009-01-01	120.5920000000000100
2010-01-01	85.1138000000000000
2011-01-01	90.4596000000000000
2012-01-01	74.5239000000000000