Year	billion cubic meters
2002	0.8992
2003	0.9073333333
2004	0.9154666667
2005	0.9236
2006	0.9295
2007	0.9354
2008	1.04
2009	0.9427
2010	0.9255
2011	0.8503
2012	0.928
2013	1.1556
2014	0.9803
2015	0.897
2016	0.8873
2017	0.9314
2018	0.961
2019	0.944
2020	1.003