Year	sq. km
1961	170
1962	170
1963	180
1964	180
1965	180
1966	180
1967	190
1968	190
1969	190
1970	190
1971	200
1972	200
1973	200
1974	199
1975	200
1976	200
1977	200
1978	200
1979	202
1980	205
1981	208
1982	210
1983	212
1984	215
1985	218
1986	212
1987	210
1988	210
1989	210
1990	209
1991	198
1992	197
1993	197
1994	195
1995	180
1996	174
1997	170
1998	155
1999	154
2000	142
2001	139
2002	131
2003	124
2004	111
2005	109
2006	101
2007	99.3
2008	99.4
2009	99.4
2010	99.4
2011	99.4
2012	99.4
2013	99.4
2014	99.4
2015	99.4
2016	99.4
2017	99.4
2018	99.4
2019	99.4
2020	99.4
2021	99.4