Year	sq. km
1961	25600
1962	25600
1963	25600
1964	25600
1965	25600
1966	25600
1967	25600
1968	25600
1969	25600
1970	25600
1971	25600
1972	25600
1973	25600
1974	25600
1975	25600
1976	25600
1977	25600
1978	25600
1979	25600
1980	25600
1981	25600
1982	25600
1983	25600
1984	25600
1985	25600
1986	25600
1987	25600
1988	25600
1989	25600
1990	25600
1991	25600
1992	25600
1993	25570
1994	25570
1995	25560
1996	25560
1997	25560
1998	25560
1999	25570
2000	25440
2001	25390
2002	25340
2003	25280
2004	25220
2005	24990
2006	24830
2007	24850
2008	24810
2009	24720
2010	24650
2011	24620
2012	24600
2013	24610
2014	23150
2015	23180
2016	23179
2017	23173
2018	22571
2019	22616
2020	22646
2021	22750