Year	Percent
1960-01-01	92.98780000000000
1961-01-01	92.82410000000000
1962-01-01	93.63180000000000
1963-01-01	94.70250000000000
1964-01-01	95.11270000000000
1965-01-01	95.47640000000000
1966-01-01	95.78780000000000
1967-01-01	96.27250000000000
1968-01-01	96.90760000000000
1969-01-01	94.70810000000000
1970-01-01	91.87360000000000
1971-01-01	92.27630000000000
1972-01-01	93.46360000000000
1973-01-01	94.22370000000000
1974-01-01	88.91540000000000
1975-01-01	78.18600000000000
1976-01-01	79.68430000000000
1977-01-01	83.50750000000000
1978-01-01	80.28650000000000
1979-01-01	77.87130000000000
1980-01-01	80.51570000000000
1981-01-01	83.68290000000000
1982-01-01	81.84770000000000
1983-01-01	80.61510000000000
1984-01-01	79.07790000000000
1985-01-01	76.73870000000000
1986-01-01	75.57910000000000
1987-01-01	77.15180000000000
1988-01-01	80.66960000000000
1989-01-01	83.31460000000000
1990-01-01	85.54790000000000
1991-01-01	92.29740000000000
1992-01-01	96.73800000000000
1993-01-01	96.95480000000000
1994-01-01	97.38090000000000
1995-01-01	97.81940000000000
1996-01-01	98.19790000000000
1997-01-01	98.50170000000000
1998-01-01	99.03810000000000
1999-01-01	99.56110000000000
2000-01-01	99.87000000000000
2001-01-01	99.88680000000000
2002-01-01	99.88950000000000
2003-01-01	99.89200000000001
2004-01-01	99.91300000000000
2005-01-01	99.93520000000000
2006-01-01	99.94030000000000
2007-01-01	99.94610000000000
2008-01-01	99.95350000000000
2009-01-01	99.95890000000000
2010-01-01	99.77640000000000
2011-01-01	99.54680000000000
2012-01-01	99.49300000000000
2013-01-01	99.50210000000000
2014-01-01	99.53790000000000
2015-01-01	97.63810000000000
2016-01-01	93.61240000000000