Year billion cubic meters 1996 1.555 1997 1.33925 1998 1.1235 1999 0.90775 2000 0.692 2001 0.6626 2002 0.6332 2003 0.8077333333 2004 0.9822666667 2005 1.1568 2006 0.854 2007 0.5512 2008 0.79915 2009 1.0471 2010 0.909 2011 0.7709 2012 0.6328 2013 0.4947 2014 0.6777413333 2015 0.8607826667 2016 1.043824 2017 1.598767 2018 2.15371 2019 1.59918 2020 1.59918