Year	% of land area
1961	0.34928396786587496
1962	0.38809329762874994
1963	0.42690262739162493
1964	0.4657119571544999
1965	0.504521286917375
1966	0.54333061668025
1967	0.582139946443125
1968	0.6209492762059999
1969	0.6597586059688749
1970	0.6985679357317499
1971	0.7373772654946249
1972	0.7761865952574999
1973	0.8149959250203749
1974	0.8538052547832499
1975	0.9003764504987
1976	1.0012807078821748
1977	1.0594947025264874
1978	1.1138277641945125
1979	1.1215896301470873
1980	1.1293514960996625
1981	1.1371133620522373
1982	1.1448752280048122
1983	1.1526370939573873
1984	1.1603989599099624
1985	1.1681608258625373
1986	1.1759226918151124
1987	1.1836845577676873
1988	1.1914464237202624
1989	1.1992082896728373
1990	1.2069701556254122
1991	1.2147320215779873
1992	1.2224938875305624
1993	1.2302557534831373
1994	1.2380176194357124
1995	1.2613032172934373
1996	1.2613032172934373
1997	1.2613032172934373
1998	1.2613032172934373
1999	1.2613032172934373
2000	1.2613032172934373
2001	1.2613032172934373
2002	1.2613032172934373
2003	1.2613032172934373
2004	1.2613032172934373
2005	1.2613032172934373
2006	1.2613032172934373
2007	1.2613032172934373
2008	1.2613032172934373
2009	1.2613032172934373
2010	1.2613032172934373
2011	1.2613032172934373
2012	1.2613032172934373
2013	1.2613032172934373
2014	1.2613032172934373
2015	1.2613032172934373
2016	1.2613032172934373
2017	1.2613032172934373
2018	1.2613032172934373
2019	1.2613032172934373
2020	1.2613032172934373
2021	1.2613032172934373