Year	% of land area
1961	9.019165727170236
1962	9.019165727170236
1963	9.131905298759865
1964	9.019165727170236
1965	9.019165727170236
1966	9.019165727170236
1967	9.019165727170236
1968	9.019165727170236
1969	7.891770011273957
1970	7.891770011273957
1971	7.891770011273957
1972	7.891770011273957
1973	7.328072153325817
1974	7.328072153325817
1975	7.328072153325817
1976	7.328072153325817
1977	7.328072153325817
1978	7.328072153325817
1979	7.328072153325817
1980	7.328072153325817
1981	7.328072153325817
1982	7.328072153325817
1983	7.328072153325817
1984	7.328072153325817
1985	7.328072153325817
1986	7.328072153325817
1987	7.328072153325817
1988	5.749718151071026
1989	5.636978579481398
1990	5.636978579481398
1991	5.636978579481398
1992	5.2987598647125145
1993	5.2987598647125145
1994	4.96054114994363
1995	4.96054114994363
1996	4.96054114994363
1997	4.96054114994363
1998	4.96054114994363
1999	4.96054114994363
2000	4.735062006764374
2001	4.509582863585118
2002	4.509582863585118
2003	4.509582863585118
2004	4.3968432919954905
2005	4.1713641488162345
2006	4.1713641488162345
2007	4.1713641488162345
2008	3.9458850056369785
2009	3.720405862457723
2010	3.494926719278467
2011	3.3821871476888385
2012	3.269447576099211
2013	3.0439684329199546
2014	2.818489289740699
2015	2.593010146561443
2016	2.367531003382187
2017	2.142051860202931
2018	1.8038331454340473
2019	1.8038331454340473
2020	1.8038331454340473
2021	1.8038331454340473