Year % of total final energy consumption 1990 4.3 1991 4.5 1992 4 1993 4.2 1994 3.3 1995 3.7 1996 3.6 1997 3.8 1998 3.8 1999 3.7 2000 3.7 2001 3.5 2002 3.7 2003 4.2 2004 4.3 2005 4 2006 4.4 2007 4.3 2008 4.4 2009 4.5 2010 4.7 2011 4.8 2012 4.7 2013 5 2014 5.6 2015 6.2 2016 6.4 2017 6.9 2018 7.3 2019 7.8 2020 8.5 2021 8.8