Year Percent 1973-01-01 8.266666666000040 1974-01-01 12.992610837518700 1975-01-01 8.392370572184480 1976-01-01 5.235042735323740 1977-01-01 9.889519259331040 1978-01-01 8.689745122748390 1979-01-01 7.049999999250090 1980-01-01 6.928226685631900 1981-01-01 7.374781595838090 1982-01-01 7.776798426908510 1983-01-01 4.718168092751540 1984-01-01 1.177460050466690 1985-01-01 1.490321814278770 1986-01-01 0.953606740192035 1987-01-01 0.654844691701642 1988-01-01 1.468132880419150 1989-01-01 3.342033590557940 1990-01-01 9.833635315434000 1991-01-01 9.058188362327570 1992-01-01 -0.545471213788200 1993-01-01 0.382541365165906 1994-01-01 2.534435261707910 1995-01-01 2.686727565824860 1996-01-01 3.553985696842860 1997-01-01 0.682191434707608 1998-01-01 0.129658287674047 1999-01-01 2.990810359231650 2000-01-01 1.812946138870870 2001-01-01 1.300000000000010 2002-01-01 0.888450148074899 2003-01-01 0.961350293542095 2004-01-01 1.248564436798930 2005-01-01 4.142975836310210 2006-01-01 3.057013391667240 2007-01-01 5.484949832775940 2008-01-01 10.582709786514500 2009-01-01 4.609595484477860 2010-01-01 4.496402877697870 2011-01-01 4.839403498709500 2012-01-01 3.255146002872190 2013-01-01 2.682296840850380 2014-01-01 2.908926728586180 2015-01-01 3.271701660921340 2016-01-01 3.198397766583710 2017-01-01 2.171832985100080