Year Units 1960-01-01 4109.46746023392 1961-01-01 5652.70521065248 1962-01-01 6787.23682093794 1963-01-01 7474.13789679190 1964-01-01 10368.93528789070 1965-01-01 13025.77052056870 1966-01-01 20497.45519923260 1967-01-01 23716.07738323400 1968-01-01 25340.10778400300 1969-01-01 30884.38075339570 1970-01-01 32645.79136933550 1971-01-01 35413.83915715170 1972-01-01 41434.85418276210 1973-01-01 48668.57670300510 1974-01-01 47078.07361665280 1975-01-01 46790.06580841970 1976-01-01 50673.42833118510 1977-01-01 54204.59050470000 1978-01-01 53482.85373142780 1979-01-01 50753.15792034670 1980-01-01 46950.42450005660 1981-01-01 41363.05666554790 1982-01-01 43811.45013127920 1983-01-01 45005.75848995150 1984-01-01 42704.72165977830 1985-01-01 47024.18459177330 1986-01-01 56348.45782680280 1987-01-01 75882.12539746220 1988-01-01 88654.06961571540 1989-01-01 93963.81493206650 1990-01-01 82347.50000000000 1991-01-01 73915.25000000000 1992-01-01 81837.00000000000 1993-01-01 61991.75000000000 1994-01-01 75806.83333333330 1995-01-01 69530.75000000000 1996-01-01 75910.66666666670 1997-01-01 84698.58333333330 1998-01-01 99377.50000000000 1999-01-01 117187.16666666700 2000-01-01 115104.66666666700 2001-01-01 118797.75000000000 2002-01-01 110989.75000000000 2003-01-01 115175.75000000000 2004-01-01 126440.50000000000 2005-01-01 127406.41666666700 2006-01-01 136217.33333333300 2007-01-01 134569.58333333300 2008-01-01 96764.66666666670 2009-01-01 79397.66666666670 2010-01-01 81834.58333333330 2011-01-01 67337.58333333330 2012-01-01 58299.08333333330 2013-01-01 60224.08333333330 2014-01-01 71275.66666666670 2015-01-01 86186.00000000000 2016-01-01 95589.33333333330 2017-01-01 102910.91666666700