Year	% of land area
1961	0.9852216748768473
1962	0.9852216748768473
1963	0.9852216748768473
1964	0.9852216748768473
1965	0.9852216748768473
1966	1.477832512315271
1967	1.9704433497536946
1968	1.9704433497536946
1969	1.9704433497536946
1970	2.4630541871921183
1971	2.4630541871921183
1972	2.955665024630542
1973	2.955665024630542
1974	2.955665024630542
1975	3.4482758620689653
1976	3.4482758620689653
1977	3.4482758620689653
1978	3.4482758620689653
1979	3.4482758620689653
1980	3.4482758620689653
1981	3.4482758620689653
1982	3.4482758620689653
1983	3.4482758620689653
1984	3.4482758620689653
1985	3.4482758620689653
1986	3.4482758620689653
1987	3.4482758620689653
1988	2.955665024630542
1989	2.955665024630542
1990	2.955665024630542
1991	2.955665024630542
1992	2.955665024630542
1993	2.955665024630542
1994	2.4630541871921183
1995	2.4630541871921183
1996	2.4630541871921183
1997	2.4630541871921183
1998	1.9704433497536946
1999	1.9704433497536946
2000	1.9704433497536946
2001	1.9704433497536946
2002	1.9704433497536946
2003	1.9704433497536946
2004	1.9704433497536946
2005	1.9704433497536946
2006	1.9704433497536946
2007	1.9704433497536946
2008	1.9704433497536946
2009	1.9704433497536946
2010	1.9704433497536946
2011	2.0030045067601403
2012	2.0030045067601403
2013	2.0030045067601403
2014	2.0030045067601403
2015	2.0030045067601403
2016	2.0030045067601403
2017	2.0030045067601403
2018	2.0030045067601403
2019	2.0030045067601403
2020	2.0030045067601403
2021	2.0030045067601403