Year	sq. km
1961	10676712.145
1962	10731399.115
1963	10793744.782
1964	10856138.596
1965	10941196.61
1966	10987997.857
1967	11054903.739
1968	11333919.911
1969	11351250.888999999
1970	11228831.385
1971	11326590.766999999
1972	11390339.6
1973	11433686.7
1974	11536871
1975	11587267.7
1976	11520575.833
1977	11501177.367
1978	11615610.3
1979	11626622.4
1980	11703251.3
1981	11766544.2
1982	11815209.2
1983	11855956.7
1984	11988502.5
1985	12143748.8
1986	12046394.3
1987	12160912.3
1988	12245079.3
1989	12268145.3
1990	12311207.3
1991	12321149.473
1992	12354188.519
1993	12294742.665
1994	12425292.579
1995	12375778.648
1996	12399554.655000001
1997	12482438.797
1998	12505727.017
1999	12438337.309
2000	12477103.824000001
2001	12505019.257
2002	12436829.234
2003	12224285.333
2004	11799335.678
2005	11962740.122000001
2006	11981452.667
2007	11896298.911
2008	11820897.656
2009	11787737.962
2010	11709053.4
2011	11912410.238
2012	11818075.195
2013	11665517.296
2014	11685842.561
2015	11435446.379
2016	11390070.200000001
2017	11713569.919000002
2018	11580219.903
2019	11611315.158
2020	11540148.443
2021	11622962.797