Year	sq. km
1961	20553531
1962	20553531
1963	20553531
1964	20553531
1965	20553531
1966	20553531
1967	20553531
1968	20553531
1969	20553531
1970	20553531
1971	20553531
1972	20553531
1973	20553531
1974	20553531
1975	20553531
1976	20553531
1977	20553531
1978	20553531
1979	20553531
1980	20553531
1981	20553531
1982	20553531
1983	20553531
1984	20553531
1985	20553531
1986	20553531
1987	20553531
1988	20553531
1989	20553531
1990	20553531
1991	20553531
1992	20553531
1993	20671131
1994	20671131
1995	20671131
1996	20671131
1997	20671131
1998	20671131
1999	20671131
2000	20671131
2001	20671131
2002	20671131
2003	20671131
2004	20675221.86
2005	20675221.003
2006	20675190.95
2007	20675157.677
2008	20675175.279
2009	20672107.3
2010	20672102.578
2011	20672381.619000003
2012	20691447.75
2013	20691226.908
2014	20691213.815
2015	20691266.405
2016	20691255.244
2017	20691249.018
2018	20691255.887
2019	20691259.106
2020	20691221.327
2021	20691219.327