Year	billion cubic meters
1976	27.6
1977	27.6515421053
1978	27.7030842105
1979	27.7546263158
1980	27.8061684211
1981	27.8577105263
1982	27.9092526316
1983	27.9607947368
1984	28.0126315789
1985	28.0638789474
1986	28.1157894737
1987	28.1669631579
1988	28.2185052632
1989	28.2705263158
1990	28.3214052632
1991	28.3731315789
1992	28.4246736842
1993	28.4762157895
1994	28.5277578947
1995	28.5793
1996	28.936785
1997	29.29427
1998	29.651755
1999	30.00924
2000	30.366725
2001	31.0323227273
2002	31.6979204545
2003	32.3635181818
2004	33.0291159091
2005	33.6947136364
2006	34.3603113636
2007	35.0259090909
2008	35.6915068182
2009	36.3571045455
2010	37.0227022727
2011	37.69
2012	37.69
2013	37.69
2014	37.69
2015	37.69
2016	37.69
2017	37.69
2018	37.69
2019	37.69
2020	37.69