Year	% of land area
1961	5.26955816781516
1962	5.472233481961897
1963	5.6749087961086335
1964	5.877584110255371
1965	6.080259424402108
1966	6.282934738548845
1967	6.4856100526955816
1968	6.566680178354277
1969	6.850425618159709
1970	7.377381434941224
1971	7.620591811917309
1972	7.580056749087961
1973	7.90433725172274
1974	8.755573571139037
1975	9.16092419943251
1976	9.687880016214026
1977	10.133765707336845
1978	10.133765707336845
1979	10.21483583299554
1980	10.336441021483584
1981	11.552492906364005
1982	11.552492906364005
1983	11.552492906364005
1984	11.674098094852047
1985	11.836238346169436
1986	11.998378597486827
1987	12.160518848804216
1988	12.322659100121605
1989	12.322659100121605
1990	12.322659100121605
1991	12.363194162950952
1992	12.363194162950952
1993	12.363194162950952
1994	12.363194162950952
1995	12.363194162950952
1996	12.4037292257803
1997	12.4037292257803
1998	12.4037292257803
1999	12.4037292257803
2000	12.4037292257803
2001	12.444264288609649
2002	12.444264288609649
2003	12.444264288609649
2004	12.444264288609649
2005	12.444264288609649
2006	12.444264288609649
2007	12.484799351438996
2008	12.484799351438996
2009	12.484799351438996
2010	12.484799351438996
2011	12.484799351438996
2012	12.525334414268341
2013	12.525334414268341
2014	12.525334414268341
2015	12.525334414268341
2016	12.525334414268341
2017	12.56586947709769
2018	12.56586947709769
2019	12.56586947709769
2020	14.025131738954194
2021	14.187271990271585