Year	sq. km
1961	90
1962	90
1963	90
1964	90
1965	90
1966	90
1967	90
1968	90
1969	89
1970	89
1971	89
1972	89
1973	88
1974	88
1975	88
1976	88
1977	88
1978	87
1979	87
1980	87
1981	87
1982	87
1983	86
1984	86
1985	86
1986	86
1987	86
1988	85
1989	85
1990	85
1991	85
1992	85
1993	84
1994	84
1995	84
1996	84
1997	81
1998	80
1999	79
2000	79
2001	75
2002	74
2003	74
2004	75
2005	76
2006	84
2007	82
2008	81
2009	88
2010	91.1
2011	96.1
2012	95.6
2013	94.6
2014	95.2
2015	92.6
2016	92.9
2017	92.2
2018	85.7
2019	85.7
2020	85.7
2021	85.7