Year	% of land area
1961	0.7094714437743881
1962	0.7094714437743881
1963	0.7094714437743881
1964	0.7094714437743881
1965	0.7094714437743881
1966	0.7094714437743881
1967	0.7094714437743881
1968	0.7094714437743881
1969	0.7538134090102874
1970	0.7538134090102874
1971	0.7538134090102874
1972	0.7538134090102874
1973	0.7538134090102874
1974	0.7538134090102874
1975	0.7538134090102874
1976	0.7538134090102874
1977	0.7538134090102874
1978	0.7538134090102874
1979	0.7538134090102874
1980	0.7538134090102874
1981	0.7538134090102874
1982	0.7981553742461865
1983	0.7981553742461865
1984	0.7981553742461865
1985	0.8868393047179851
1986	0.8868393047179851
1987	0.8868393047179851
1988	0.8868393047179851
1989	0.8868393047179851
1990	0.9311812699538844
1991	0.9755232351897837
1992	1.0198652004256827
1993	1.0642071656615821
1994	1.3302589570769776
1995	1.596310748492373
1996	1.8623625399077688
1997	2.1284143313231643
1998	2.2170982617949626
1999	2.305782192266761
2000	2.3501241575026603
2001	2.3501241575026603
2002	2.3501241575026603
2003	2.36786094359702
2004	2.36786094359702
2005	2.483150053210358
2006	2.571833983682157
2007	2.660517914153955
2008	4.434196523589925
2009	5.32103582830791
2010	5.32103582830791
2011	5.32103582830791
2012	5.32103582830791
2013	6.207875133025896
2014	6.207875133025896
2015	6.207875133025896
2016	5.32103582830791
2017	5.32103582830791
2018	5.32103582830791
2019	5.32103582830791
2020	5.32103582830791
2021	5.32103582830791