Year billion cubic meters 1993 0.007 1994 0.008473913 1995 0.0099478261 1996 0.0114217391 1997 0.0128956522 1998 0.0143695652 1999 0.0158434783 2000 0.0173173913 2001 0.0187913043 2002 0.0202652174 2003 0.0217391304 2004 0.0232130435 2005 0.0246869565 2006 0.0261608696 2007 0.0276347826 2008 0.0291086957 2009 0.0305826087 2010 0.0320565217 2011 0.0335304348 2012 0.0350043478 2013 0.0364782609 2014 0.0379521739 2015 0.039426087 2016 0.0409 2017 0.0409 2018 0.0409 2019 0.0409 2020 0.0409