Year	sq. km
1961	2010020
1962	2009130
1963	2011770
1964	2012490
1965	2015150
1966	2015070
1967	2021590
1968	2024820
1969	2031760
1970	2039260
1971	2060680
1972	2081020
1973	2085850
1974	2086940
1975	2077390
1976	2080320
1977	2079180
1978	2075930
1979	2087410
1980	2075460
1981	2038556
1982	2046553.4
1983	2053707.4
1984	2060893.6
1985	2064368
1986	2064798
1987	2070970
1988	2079370
1989	2075198
1990	2076092
1991	2095119
1992	2113234.8
1993	2124586.8
1994	2129449.896
1995	2130265.327
1996	2134610.4050000003
1997	2125120.5319999997
1998	2134663.175
1999	2121536.9979999997
2000	2114628.131
2001	2121635.0889999997
2002	2127353.8310000002
2003	2134868.969
2004	2143598.978
2005	1975889.159
2006	1980624.403
2007	1984869.289
2008	1961945.564
2009	1959615.5
2010	1963882
2011	1965880.364
2012	1968168.3269999998
2013	1971171.841
2014	1967825.4549999998
2015	1969043.7889999999
2016	1974606.696
2017	1982604.6330000001
2018	1982367.8569999998
2019	1974571.7260000003
2020	1983456.773
2021	1983423.47