Year	sq. km
1961	9145856.6
1962	9148056.6
1963	9156536.6
1964	9157156.6
1965	9158956.6
1966	9164086.6
1967	9166426.6
1968	9181966.6
1969	9191586.6
1970	9194776.6
1971	9212806.6
1972	9220316.6
1973	9224096.6
1974	9222316.6
1975	9234216.6
1976	9241716.6
1977	9246396.6
1978	9263516.6
1979	9268386.6
1980	9278516.6
1981	9290406.6
1982	9299966.6
1983	9313576.6
1984	9322046.6
1985	9372636.6
1986	9420046.6
1987	9444106.6
1988	9493626.6
1989	9526136.6
1990	9545776.5
1991	9576228.52
1992	9627879.142
1993	9504771.444
1994	9568543.862
1995	9632704.372
1996	9671177.538
1997	9711453.2
1998	9735317.083
1999	9783916.534
2000	9816756.063000001
2001	9853189.038
2002	9877442.818
2003	9937208.871
2004	9953818.379
2005	10035523.125
2006	10062712.927000001
2007	10102600.429
2008	10131205.725
2009	10182337.964
2010	10222831.458999999
2011	10261688.688000001
2012	10318973.091
2013	10364678.609000001
2014	10391986.796
2015	10420918.537
2016	10444995.234
2017	10468340.432
2018	10500976.834
2019	10518137.823
2020	10532028.68
2021	10542626.28