Year	% of land area
1961	4.477611940298507
1962	5.970149253731343
1963	5.970149253731343
1964	5.970149253731343
1965	5.970149253731343
1966	5.970149253731343
1967	5.970149253731343
1968	4.477611940298507
1969	4.477611940298507
1970	5.970149253731343
1971	2.9850746268656714
1972	4.477611940298507
1973	4.477611940298507
1974	2.9850746268656714
1975	2.9850746268656714
1976	2.9850746268656714
1977	2.9850746268656714
1978	2.9850746268656714
1979	2.9850746268656714
1980	2.9850746268656714
1981	2.9850746268656714
1982	2.9850746268656714
1983	2.9850746268656714
1984	2.9850746268656714
1985	2.9850746268656714
1986	2.9850746268656714
1987	2.9850746268656714
1988	2.9850746268656714
1989	1.4925373134328357
1990	1.4925373134328357
1991	1.4925373134328357
1992	1.4925373134328357
1993	1.4925373134328357
1994	1.4925373134328357
1995	1.4925373134328357
1996	1.4925373134328357
1997	1.4925373134328357
1998	1.4925373134328357
1999	1.4925373134328357
2000	1.4925373134328357
2001	1.4925373134328357
2002	1.4814814814814816
2003	0.8733624454148471
2004	1.0159651669085632
2005	0.9579100145137881
2006	0.9365994236311239
2007	1.0071942446043165
2008	0.8571428571428572
2009	0.8571428571428572
2010	0.9116809116809116
2011	0.8948863636363636
2012	0.8923512747875353
2013	0.8062234794908063
2014	0.7898448519040903
2015	0.7898448519040903
2016	0.7898448519040903
2017	0.7865168539325843
2018	0.7843137254901961
2019	0.782122905027933
2020	0.7799442896935933
2021	0.7799442896935933