Year	% of land area
1961	0.7619839290662234
1962	0.7619839290662234
1963	0.7619839290662234
1964	0.7619839290662234
1965	0.7619839290662234
1966	0.7619839290662234
1967	0.7619839290662234
1968	0.8312551953449709
1969	0.8312551953449709
1970	0.8312551953449709
1971	0.8312551953449709
1972	0.8312551953449709
1973	0.8312551953449709
1974	0.8312551953449709
1975	0.8312551953449709
1976	0.8312551953449709
1977	0.8312551953449709
1978	0.9005264616237185
1979	0.9697977279024661
1980	0.9697977279024661
1981	0.9697977279024661
1982	1.1083402604599613
1983	1.1083402604599613
1984	1.2468827930174564
1985	1.8703241895261846
1986	1.8703241895261846
1987	1.8703241895261846
1988	1.8703241895261846
1989	1.8703241895261846
1990	1.8703241895261846
1991	1.8703241895261846
1992	1.7317816569686895
1993	1.7317816569686895
1994	1.7317816569686895
1995	1.7317816569686895
1996	1.7317816569686895
1997	1.7317816569686895
1998	1.7317816569686895
1999	1.6625103906899419
2000	1.6625103906899419
2001	1.6625103906899419
2002	1.6625103906899419
2003	1.801052923247437
2004	1.8703241895261846
2005	1.9395954558049322
2006	1.9395954558049322
2007	1.9395954558049322
2008	1.9395954558049322
2009	1.9395954558049322
2010	2.0781379883624274
2011	2.28595178719867
2012	2.28595178719867
2013	2.28595178719867
2014	2.28595178719867
2015	2.28595178719867
2016	2.28595178719867
2017	2.28595178719867
2018	2.28595178719867
2019	2.28595178719867
2020	2.28595178719867
2021	2.28595178719867