Year	Percent
1960-01-01	15.90970000000000
1961-01-01	15.45500000000000
1962-01-01	14.64910000000000
1963-01-01	14.77480000000000
1964-01-01	16.66130000000000
1965-01-01	18.74160000000000
1966-01-01	21.78620000000000
1967-01-01	26.42860000000000
1968-01-01	30.99450000000000
1969-01-01	41.05950000000000
1970-01-01	47.58580000000000
1971-01-01	46.66640000000000
1972-01-01	45.89630000000000
1973-01-01	44.08390000000000
1974-01-01	42.57840000000000
1975-01-01	38.86730000000000
1976-01-01	33.38400000000000
1977-01-01	31.32520000000000
1978-01-01	30.44840000000000
1979-01-01	31.74960000000000
1980-01-01	38.96090000000000
1981-01-01	47.06970000000000
1982-01-01	53.34210000000000
1983-01-01	60.94910000000000
1984-01-01	66.13640000000000
1985-01-01	68.09880000000000
1986-01-01	69.77350000000000
1987-01-01	72.26980000000000
1988-01-01	74.10240000000000
1989-01-01	75.85700000000000
1990-01-01	79.55000000000000
1991-01-01	85.33240000000000
1992-01-01	87.80630000000000
1993-01-01	87.62510000000000
1994-01-01	85.67540000000000
1995-01-01	82.88600000000001
1996-01-01	83.12510000000000
1997-01-01	82.17270000000000
1998-01-01	80.66140000000000
1999-01-01	80.86370000000000
2000-01-01	83.08270000000000
2001-01-01	84.96520000000000
2002-01-01	80.93230000000000
2003-01-01	74.63970000000000
2004-01-01	73.93780000000000
2005-01-01	76.72160000000000
2006-01-01	87.33130000000000
2007-01-01	85.73380000000000
2008-01-01	85.16300000000000
2009-01-01	91.25860000000000
2010-01-01	93.86600000000000
2011-01-01	94.59640000000000
2012-01-01	92.53750000000000
2013-01-01	85.82060000000000
2014-01-01	72.81830000000000
2015-01-01	61.84350000000000
2016-01-01	57.06210000000000