Year	% of land area
1961	0.7876878332525449
1962	0.7876878332525449
1963	0.7876878332525449
1964	0.8119243819680078
1965	0.8240426563257393
1966	0.8482792050412021
1967	0.8482792050412021
1968	0.8603974793989336
1969	1.1512360639844887
1970	1.1512360639844887
1971	1.139117789626757
1972	1.139117789626757
1973	1.187590887057683
1974	1.187590887057683
1975	1.187590887057683
1976	1.187590887057683
1977	1.187590887057683
1978	1.187590887057683
1979	1.1997091614154143
1980	1.1997091614154143
1981	1.1997091614154143
1982	1.1997091614154143
1983	0.9331071255453223
1984	0.9331071255453223
1985	0.9331071255453223
1986	0.896752302472128
1987	0.896752302472128
1988	0.896752302472128
1989	0.896752302472128
1990	0.9573436742607853
1991	0.9573436742607853
1992	0.8482792050412021
1993	0.9573436742607853
1994	0.9209888511875909
1995	0.9452253999030538
1996	0.9209888511875909
1997	0.8846340281143965
1998	0.872515753756665
1999	0.8603974793989336
2000	0.8603974793989336
2001	0.8603974793989336
2002	0.8603974793989336
2003	0.8603974793989336
2004	0.7998061076102764
2005	0.7998061076102764
2006	0.8240426563257393
2007	0.8240426563257393
2008	0.8034415899175957
2009	0.8034415899175957
2010	0.7913233155598642
2011	0.7913233155598642
2012	0.7913233155598642
2013	0.7925351429956375
2014	0.7925351429956375
2015	0.7936257876878332
2016	0.8103490063015026
2017	0.8103490063015026
2018	0.8103490063015026
2019	0.8103490063015026
2020	0.820576829859428
2021	0.820576829859428