Year	% of land area
1961	7.292808973929147
1962	7.328100059586733
1963	7.390394284286082
1964	7.430123096907284
1965	7.456826716765262
1966	7.497698257052034
1967	7.525965199849058
1968	7.592574922316716
1969	7.636065453734087
1970	7.616608814396985
1971	7.651166524882722
1972	7.746333772762665
1973	7.799869085036638
1974	7.865685551557802
1975	7.871266372298021
1976	7.966774411337377
1977	8.07743480028136
1978	8.176366331496045
1979	8.279959788173704
1980	8.35847564055257
1981	8.427247252715574
1982	8.581704103341712
1983	8.783716646295058
1984	9.036844534835451
1985	9.317651590715158
1986	9.3370286144231
1987	9.372481922118954
1988	9.36955627176495
1989	9.38722805055234
1990	9.407750890777427
1991	9.37828058913606
1992	9.195174957357269
1993	9.116195912161112
1994	9.046343103764066
1995	9.00179528273213
1996	8.975624084595745
1997	9.010472716498766
1998	8.99431386810464
1999	9.00677802044191
2000	8.982373538572727
2001	8.98840151342213
2002	8.998401957925456
2003	9.038528883002249
2004	9.08081786737263
2005	9.118785315134645
2006	9.176578125164779
2007	9.201474453108247
2008	9.166959839508046
2009	9.142838472291514
2010	9.196425153699384
2011	9.179047865139687
2012	9.182121437687815
2013	9.173390728546355
2014	9.165149258406878
2015	9.188092711770507
2016	9.176611954626825
2017	9.154334299447445
2018	9.131600444741263
2019	9.106406786584293
2020	9.161163122398875
2021	9.187925054345179