Year	Percent
1960-01-01	84.32660000000000
1961-01-01	81.53220000000000
1962-01-01	76.57990000000000
1963-01-01	73.31270000000000
1964-01-01	100.77700000000000
1965-01-01	144.16400000000000
1966-01-01	140.52600000000000
1967-01-01	131.76000000000000
1968-01-01	117.45299999999999
1969-01-01	104.46200000000000
1970-01-01	100.49300000000000
1971-01-01	95.29230000000000
1972-01-01	81.64920000000000
1973-01-01	71.90750000000000
1974-01-01	68.96060000000000
1975-01-01	69.09170000000000
1976-01-01	69.29800000000000
1977-01-01	55.95520000000000
1978-01-01	57.67090000000000
1979-01-01	71.95370000000000
1980-01-01	74.10880000000000
1981-01-01	73.30720000000000
1982-01-01	72.86260000000000
1983-01-01	69.96740000000000
1984-01-01	65.44610000000000
1985-01-01	56.95220000000000
1986-01-01	50.67230000000000
1987-01-01	45.74420000000000
1988-01-01	38.07670000000000
1989-01-01	35.70320000000000
1990-01-01	37.05770000000000
1991-01-01	39.53900000000000
1992-01-01	40.02090000000000
1993-01-01	40.02090000000000
1994-01-01	27.94290000000000
1995-01-01	28.97730000000000
1996-01-01	28.66750000000000
1997-01-01	27.50330000000000
1998-01-01	27.50330000000000
1999-01-01	33.68530000000000
2000-01-01	32.64920000000000
2001-01-01	23.08520000000000
2002-01-01	21.48150000000000
2003-01-01	19.89320000000000
2004-01-01	19.22790000000000
2005-01-01	18.15330000000000
2006-01-01	17.79470000000000
2007-01-01	18.33660000000000
2008-01-01	20.38510000000000
2009-01-01	24.89990000000000
2010-01-01	27.61030000000000
2011-01-01	25.74980000000000
2012-01-01	26.25500000000000
2013-01-01	26.81660000000000
2014-01-01	25.19340000000000
2015-01-01	23.98520000000000
2016-01-01	24.47450000000000