Year	% of land area
1961	0.9803921568627451
1962	0.9803921568627451
1963	0.9803921568627451
1964	0.9803921568627451
1965	0.9803921568627451
1966	0.9803921568627451
1967	0.9803921568627451
1968	0.9803921568627451
1969	0.9803921568627451
1970	0.9803921568627451
1971	0.9803921568627451
1972	0.9803921568627451
1973	0.9803921568627451
1974	0.9803921568627451
1975	0.9900990099009901
1976	0.9900990099009901
1977	1
1981	1
1982	1.0101010101010102
1983	1.0101010101010102
1984	1.0101010101010102
1985	1.0101010101010102
1986	1.0101010101010102
1987	1.0101010101010102
1988	1.0101010101010102
1989	1.0101010101010102
1990	1.0101010101010102
1991	1.0101010101010102
1992	1.0101010101010102
1993	1.0101010101010102
1994	1.0101010101010102
1995	0.9523809523809524
1996	0.9523809523809524
1997	0.9523809523809524
1998	0.9523809523809524
1999	0.9523809523809524
2000	0.9523809523809524
2001	0.9523809523809524
2002	0.9523809523809524
2003	0.9523809523809524
2004	0.9523809523809524
2005	0.9523809523809524
2006	0.9523809523809524
2007	0.9523809523809524
2008	0.9523809523809524
2009	0.9523809523809524
2010	0.9523809523809524
2011	0.9523809523809524
2012	0.9523809523809524
2013	0.9523809523809524
2014	0.9523809523809524
2015	0.9523809523809524
2016	0.9523809523809524
2017	0.9523809523809524
2018	0.9523809523809524
2019	0.9523809523809524
2020	0.9523809523809524
2021	0.9523809523809524