Year	% of land area
1961	9.940903246342796
1962	9.980160795131805
1963	10.060270799807382
1964	10.106063807253866
1965	10.161498943215726
1966	10.208104917514998
1967	10.256833251248137
1968	10.306120586845962
1969	10.307160152521355
1970	10.334919728437859
1971	10.338846337420014
1972	10.430501203493696
1973	10.507646218967846
1974	10.545445120871353
1975	10.573487723152365
1976	10.639818912296557
1977	10.710460127260545
1978	10.810056270999937
1979	10.886909051498224
1980	10.90756660321497
1981	10.953186464081094
1982	11.107836726822743
1983	11.191071604929796
1984	11.40179765915844
1985	11.610267774181835
1986	11.608231263812437
1987	11.670266157225969
1988	11.66846055210326
1989	11.716184446607796
1990	11.713873349513015
1991	11.738176768059358
1992	11.340651687749993
1993	11.299173149677317
1994	11.268635715985418
1995	11.2657797399275
1996	11.238340738888974
1997	11.278465506391749
1998	11.278303271259187
1999	11.304427660583249
2000	11.259705546736305
2001	11.279760118474018
2002	11.29013937715409
2003	11.327070614929191
2004	11.348630134653536
2005	11.376243232323139
2006	11.420051080890028
2007	11.44001413573859
2008	11.421286844793867
2009	11.438315327940005
2010	11.45451445915396
2011	11.46692019174049
2012	11.476556724508503
2013	11.48552231728958
2014	11.475902498338218
2015	11.510631268511911
2016	11.526808515481688
2017	11.524958449010056
2018	11.514463890016865
2019	11.48634041255005
2020	11.536166870772721
2021	11.548482471297467