Year	% of land area
1961	2.140273526956745
1962	2.140273526956745
1963	2.140273526956745
1964	2.140273526956745
1965	2.140273526956745
1966	2.140273526956745
1967	2.140273526956745
1968	2.140273526956745
1969	2.140273526956745
1970	2.3543008796524196
1971	2.3543008796524196
1972	2.3543008796524196
1973	2.3543008796524196
1974	2.4613145560002567
1975	2.4613145560002567
1976	2.5683282323480943
1977	2.5683282323480943
1978	2.5683282323480943
1979	2.6753419086959314
1980	2.7823555850437685
1981	2.7823555850437685
1982	2.889369261391606
1983	3.10339661408728
1984	3.10339661408728
1985	3.10339661408728
1986	3.10339661408728
1987	3.1247993493568478
1988	3.0177856730090107
1989	2.846563790852471
1990	2.889369261391606
1991	2.889369261391606
1992	2.889369261391606
1993	2.910771996661173
1994	3.5175879396984926
1995	3.6683417085427132
1996	3.7939698492462313
1997	3.8442211055276383
1998	3.8442211055276383
1999	3.8442211055276383
2000	3.869346733668342
2001	3.8944723618090453
2002	3.919597989949749
2003	3.9447236180904524
2004	4.145132093291707
2005	4.381247212529842
2006	3.96935750452554
2007	3.5758323057953145
2008	2.6235013248681693
2009	2.6235013248681693
2010	2.639242332817378
2011	2.6287483275179055
2012	2.6287483275179055
2013	2.6287483275179055
2014	2.6287483275179055
2015	2.6287483275179055
2016	2.6216442953020134
2017	2.4774538590604025
2018	2.464604090194022
2019	2.464604090194022
2020	2.464604090194022
2021	2.464604090194022