Year	sq. km
1961	13740
1962	13740
1963	13740
1964	13740
1965	13740
1966	13740
1967	13740
1968	13740
1969	13740
1970	13740
1971	13740
1972	13740
1973	13740
1974	13740
1975	13740
1976	13740
1977	13740
1978	13740
1979	13740
1980	13740
1981	13740
1982	13740
1983	13740
1984	13740
1985	13740
1986	13740
1987	13740
1988	13740
1989	13740
1990	13740
1991	13740
1992	13740
1993	13200
1994	11010
1995	9910
1996	10050
1997	10230
1998	10430
1999	10010
2000	9860
2001	8900
2002	6982
2003	8287
2004	7704
2005	8819
2006	8985
2007	9146
2008	9068
2009	9318
2010	9488
2011	9460
2012	9559
2013	9650
2014	9740
2015	9930
2016	10030
2017	9820
2018	9850
2019	9884
2020	9850
2021	9870