Year Percent 1960-01-01 4.452580000000000000 1961-01-01 5.797200000000000000 1962-01-01 7.413150000000000000 1963-01-01 7.465860000000000000 1964-01-01 7.053939999999999000 1965-01-01 6.060150000000000000 1966-01-01 4.208140000000000000 1967-01-01 2.196840000000000300 1968-01-01 1.218740000000000000 1969-01-01 3.591350000000000000 1970-01-01 5.835590000000000000 1971-01-01 5.758230000000000000 1972-01-01 3.283509999999999700 1973-01-01 0.925709000000000000 1974-01-01 0.207931000000000000 1975-01-01 0.123405000000000000 1976-01-01 1.945820000000000000 1977-01-01 1.813340000000000200 1978-01-01 0.012459999999999999 1979-01-01 0.008339000000000000 1980-01-01 0.019520000000000000 1981-01-01 0.035344000000000000 1982-01-01 0.041022000000000000 1983-01-01 0.085137000000000000 1984-01-01 0.127518000000000020 1985-01-01 0.087422000000000000 1986-01-01 0.048648000000000004 1987-01-01 0.361917000000000000 1988-01-01 0.446395000000000000 1989-01-01 0.321248000000000000 1990-01-01 1.518930000000000000 1991-01-01 4.480980000000001000 1992-01-01 6.200950000000000000 1993-01-01 3.923780000000000300 1994-01-01 2.511180000000000000 1995-01-01 4.074370000000000000 1996-01-01 5.177810000000000000 1997-01-01 4.594990000000000000 1998-01-01 2.703010000000000000 1999-01-01 0.938499000000000000 2000-01-01 0.430233000000000000 2001-01-01 0.410880000000000000 2002-01-01 0.261476000000000040 2003-01-01 0.341703000000000030 2004-01-01 0.780928000000000000 2005-01-01 0.770598999999999900 2006-01-01 0.952637000000000100 2007-01-01 2.442130000000000000 2008-01-01 3.930040000000000000 2009-01-01 4.022850000000000000 2010-01-01 3.776880000000000200 2011-01-01 4.596060000000000000 2012-01-01 4.589060000000000000 2013-01-01 4.198710000000000000 2014-01-01 4.350540000000000500 2015-01-01 5.988430000000000000 2016-01-01 9.041039999999999000