Year	sq. km
1961	40
1962	40
1963	40
1964	40
1965	40
1966	40
1967	40
1968	40
1969	40
1970	40
1971	40
1972	40
1973	40
1974	40
1975	40
1976	40
1977	40
1978	40
1979	40
1980	40
1981	40
1982	40
1983	40
1984	40
1985	40
1986	40
1987	40
1988	40
1989	40
1990	40
1991	40
1992	40
1993	40
1994	40
1995	40
1996	40
1997	40
1998	30
1999	30
2000	30
2001	30
2002	30
2003	30
2004	30
2005	30
2006	30
2007	17
2008	17
2009	17
2010	17
2011	17
2012	17
2013	17
2014	17
2015	17
2016	17
2017	17
2018	5.4
2019	5.4
2020	5.4
2021	5.4