Year	sq. km
1961	907660
1962	907660
1963	907660
1964	907660
1965	907660
1966	907660
1967	907660
1968	907660
1969	907660
1970	907660
1971	907660
1972	907660
1973	907660
1974	907660
1975	907660
1976	907660
1977	907660
1978	907660
1979	907660
1980	907660
1981	907660
1982	907660
1983	907660
1984	907660
1985	907660
1986	907660
1987	907660
1988	907660
1989	907660
1990	907660
1991	907660
1992	22297355
1993	22293629
1994	22288755
1995	22285785
1996	22285351
1997	22286032
1998	22288521
1999	22295340
2000	22298628
2001	22297669
2002	22296328
2003	22296325
2004	22296560
2005	22296652
2006	22393931
2007	22393804
2008	22392906
2009	22392815
2010	22392760
2011	22392687
2012	22392677
2013	22392696
2014	22391561
2015	22396381
2016	22396389
2017	22396398
2018	22396476.3
2019	22396429.9
2020	22393160.6
2021	22393223