Year	cubic meters
1961	22739.367749831847
1962	22614.297420065734
1963	22487.19413470855
1964	22319.8144870998
1965	22110.583172449748
1966	21901.184162446847
1967	21733.79507268175
1968	21611.994429413644
1969	21460.649451962785
1970	21261.24965668055
1971	21115.4541168591
1972	21053.14996983613
1973	21016.893157489536
1974	20955.99791910617
1975	20872.90997782467
1976	20797.13597897227
1977	20723.40435845915
1978	20663.156830097738
1979	20618.114182875197
1980	20576.302525073308
1981	20551.642130289478
1982	20539.891652672115
1983	20530.594608041534
1984	20511.94700960403
1985	20478.09526409917
1986	20430.524924702764
1987	20362.46618758904
1988	20269.095354714504
1989	20134.313532943266
1990	19979.35466684426
1991	19843.629875687202
1992	19727.58170881697
1993	19613.328392150954
1994	19474.42956150076
1995	19372.51407311187
1996	19341.707802671146
1997	19330.635485032777
1998	19319.907616947014
1999	19304.858028009883
2000	19273.884033660994
2001	19222.208732952935
2002	19159.75402909459
2003	19088.594408559995
2004	19013.666601026893
2005	18937.77468079329
2006	18831.551769422516
2007	18692.42241988821
2008	18547.367971211883
2009	18390.03324724432
2010	18233.920081687964
2011	18096.745199838337
2012	17963.366078483734
2013	17811.7968051053
2014	17635.93853617585
2015	17450.429045841152
2016	17232.54411304549
2017	17001.90242339748
2018	16805.543352700002
2019	16636.042404201933
2020	16516.24648112193