Year Percent 1962-01-01 5.390510000000000 1963-01-01 7.260680000000001 1964-01-01 7.939189999999999 1965-01-01 8.974700000000000 1966-01-01 9.396960000000000 1967-01-01 9.506240000000000 1968-01-01 12.145100000000000 1969-01-01 13.614800000000000 1970-01-01 13.260200000000000 1971-01-01 10.275000000000000 1972-01-01 12.009600000000000 1973-01-01 13.020600000000000 1974-01-01 9.628830000000000 1975-01-01 12.755999999999998 1976-01-01 17.806200000000000 1977-01-01 26.075800000000000 1978-01-01 32.037200000000000 1979-01-01 26.675500000000000 1980-01-01 30.545900000000000 1981-01-01 44.701800000000000 1982-01-01 65.705500000000000 1983-01-01 72.854700000000000 1984-01-01 69.890500000000000 1985-01-01 72.682900000000000 1986-01-01 92.380100000000000 1987-01-01 80.680100000000000 1988-01-01 90.351200000000000 1989-01-01 74.037200000000000 1990-01-01 74.037200000000000 1991-01-01 26.583900000000000 1992-01-01 16.040800000000000 1993-01-01 15.616700000000000 1994-01-01 19.728800000000000 1995-01-01 25.281400000000000 1996-01-01 29.859900000000000 1997-01-01 40.573600000000000 1998-01-01 57.060200000000000 1999-01-01 53.205400000000000 2000-01-01 43.993200000000000 2001-01-01 52.390800000000000 2002-01-01 54.980500000000000 2003-01-01 53.361000000000004 2004-01-01 51.971200000000000 2005-01-01 46.225800000000000 2006-01-01 45.411600000000000 2007-01-01 53.075600000000000 2008-01-01 55.858100000000000 2009-01-01 78.346600000000000 2010-01-01 73.836200000000000 2011-01-01 59.494900000000000 2012-01-01 54.208100000000000 2013-01-01 57.127100000000000 2014-01-01 65.470100000000000 2015-01-01 94.529800000000000 2016-01-01 102.391000000000000