Year	% of land area
1961	24.846153846153847
1962	24.846153846153847
1963	24.916083916083917
1964	24.846153846153847
1965	24.846153846153847
1966	24.846153846153847
1967	24.944055944055943
1968	24.944055944055943
1969	24.944055944055943
1970	25.888111888111887
1971	25.888111888111887
1972	26.727272727272727
1973	27.643356643356643
1974	27.93006993006993
1975	28.034965034965037
1976	28.146853146853147
1977	28.251748251748253
1978	28.356643356643357
1979	28.46153846153846
1980	28.56643356643357
1981	28.692307692307693
1982	28.717482517482516
1983	28.742657342657342
1984	28.767832167832168
1985	28.786013986013987
1986	28.895104895104893
1987	28.913286713286713
1988	28.938461538461542
1989	28.956643356643358
1990	28.98181818181818
1991	28.999999999999996
1992	29.07832167832168
1993	29.156643356643357
1994	29.234965034965033
1995	29.31328671328671
1996	29.391608391608393
1997	29.469930069930072
1998	29.548251748251747
1999	29.626573426573426
2000	29.641437042204394
2001	29.71049877921172
2002	29.584931984652947
2003	29.487268922218345
2004	29.42448552493896
2005	29.312870596442274
2006	29.194279734914545
2007	29.06173700732473
2008	28.964073944890128
2009	28.880362748517612
2010	28.782699686083014
2011	28.78688524590164
2012	28.7478200209278
2013	28.7478200209278
2014	28.7478200209278
2015	28.7478200209278
2016	28.7478200209278
2017	28.7478200209278
2018	28.7478200209278
2019	28.7478200209278
2020	28.7478200209278
2021	28.7478200209278