Year	sq. km
1961	140
1962	140
1963	130
1964	130
1965	130
1966	130
1967	130
1968	120
1969	120
1970	120
1971	100
1972	110
1973	110
1974	90
1975	80
1976	80
1977	80
1978	80
1979	80
1980	80
1981	70
1982	60
1983	60
1984	60
1985	50
1986	40
1987	30
1988	30
1989	20
1990	20
1991	12
1992	12
1993	12
1994	12
1995	12
1996	12
1997	12
1998	12
1999	12
2000	12
2001	12
2002	12
2003	8
2004	8
2005	7.6
2006	7.5
2007	8
2008	7
2009	7
2010	7.4
2011	7.3
2012	7.3
2013	6.7
2014	6.6
2015	6.6
2016	6.6
2017	6.6
2018	6.6
2019	6.6
2020	6.6
2021	6.6