Year	sq. km
1961	11700
1962	11700
1963	11700
1964	11700
1965	11700
1966	11700
1967	11700
1968	11700
1969	11700
1970	11700
1971	11700
1972	11700
1973	11700
1974	11700
1975	11700
1976	11700
1977	11700
1978	11700
1979	11700
1980	11700
1981	11700
1982	11700
1983	11700
1984	11700
1985	11700
1986	11700
1987	11700
1988	11700
1989	11700
1990	11700
1991	11700
1992	11700
1993	11810
1994	12000
1995	12440
1996	13060
1997	13320
1998	13280
1999	13230
2000	13230
2001	13280
2002	13910
2003	14440
2004	15050
2005	16050
2006	17564
2007	17519
2008	17488
2009	17463
2010	17350
2011	16981
2012	16830
2013	16830
2014	16807
2015	16767
2016	16768
2017	16761
2018	16773
2019	16770
2020	16760
2021	16748.2