Year	sq. km
1961	8643980
1962	8643980
1963	8643980
1964	8643980
1965	8643980
1966	8643980
1967	8643980
1968	8643980
1969	8643980
1970	8643980
1971	8643980
1972	8643980
1973	8643940
1974	8643940
1975	8643940
1976	8643940
1977	8643940
1978	8643940
1979	8643940
1980	8643940
1981	8643940
1982	8643940
1983	8643940
1984	8643940
1985	8643940
1986	8643940
1987	8643940
1988	8643940
1989	8643940
1990	8643940
1991	8643940
1992	8643940
1993	8643940
1994	8643940
1995	8643940
1996	8643940
1997	8643940
1998	8643940
1999	8643940
2000	8643940
2001	8643940
2002	8643940
2003	8643750
2004	8643730
2005	8643730
2006	8643790
2007	8643800
2008	8643800
2009	8641290
2010	8641280
2011	8641280
2012	8641280
2013	8641088
2014	8641088
2015	8641089
2016	8641089
2017	8634829
2018	8634829
2019	8634843
2020	8634843
2021	8634848