Year	Percent
1960-01-01	98.55270000000000
1961-01-01	98.48070000000000
1962-01-01	98.38330000000000
1963-01-01	97.46400000000000
1964-01-01	96.65760000000000
1965-01-01	95.78180000000000
1966-01-01	95.31360000000000
1967-01-01	94.55520000000000
1968-01-01	95.29060000000000
1969-01-01	96.36820000000000
1970-01-01	96.52080000000000
1971-01-01	96.90110000000000
1972-01-01	96.88920000000000
1973-01-01	96.45750000000000
1974-01-01	97.28880000000000
1975-01-01	97.45910000000000
1976-01-01	97.67290000000000
1977-01-01	98.14880000000000
1978-01-01	98.31380000000000
1979-01-01	98.08710000000000
1980-01-01	96.78720000000000
1981-01-01	97.38440000000000
1982-01-01	97.61280000000000
1983-01-01	95.99020000000000
1984-01-01	95.02980000000000
1985-01-01	96.20630000000000
1986-01-01	97.83210000000000
1987-01-01	98.20670000000000
1988-01-01	98.31170000000000
1989-01-01	98.67940000000000
1990-01-01	98.32450000000000
1991-01-01	97.95050000000000
1992-01-01	99.10980000000000
1993-01-01	99.28260000000000
1994-01-01	99.21760000000000
1995-01-01	99.17550000000000
1996-01-01	97.34150000000000
1997-01-01	96.21890000000000
1998-01-01	96.14650000000000
1999-01-01	95.34130000000000
2000-01-01	94.34010000000000
2001-01-01	94.12530000000000
2002-01-01	96.30290000000000
2003-01-01	98.43040000000000
2004-01-01	98.59880000000000
2005-01-01	98.78280000000000
2006-01-01	99.02440000000000
2007-01-01	99.13350000000000
2008-01-01	99.35660000000000
2009-01-01	99.57000000000000
2010-01-01	99.64280000000000
2011-01-01	99.73230000000000
2012-01-01	99.76570000000000
2013-01-01	99.77799999999999
2014-01-01	99.79400000000000
2015-01-01	99.82880000000000
2016-01-01	99.78630000000000