Year	% of land area
1961	8.158921603405462
1962	8.33628946434906
1963	8.513657325292657
1964	8.691025186236253
1965	8.86839304717985
1966	9.134444838595247
1967	9.48918056048244
1968	9.755232351897835
1969	10.464703795672223
1970	10.64207165661582
1971	11.085491308974813
1972	11.35154310039021
1973	11.528910961333807
1974	11.794962752749202
1975	12.149698474636397
1976	12.415750266051791
1977	12.681802057467188
1978	12.859169918410785
1979	13.036537779354381
1980	13.302589570769777
1981	13.568641362185172
1982	13.74600922312877
1983	13.834693153600567
1984	13.923377084072367
1985	14.012061014544164
1986	14.100744945015965
1987	14.189428875487762
1988	14.27811280595956
1989	14.36679673643136
1990	14.322454771195458
1991	14.36679673643136
1992	14.455480666903156
1993	14.632848527846754
1994	15.076268180205746
1995	15.874423554451933
1996	17.29336644200071
1997	18.623625399077685
1998	19.953884356154663
1999	20.397304008513657
2000	21.106775452288044
2001	21.727562965590636
2002	22.61440227030862
2003	23.501241575026604
2004	23.501241575026604
2005	23.536715147215325
2006	22.170982617949626
2007	22.170982617949626
2008	22.170982617949626
2009	22.170982617949626
2010	22.170982617949626
2011	22.170982617949626
2012	23.057821922667614
2013	23.9446612273856
2014	23.9446612273856
2015	23.9446612273856
2016	24.831500532103583
2017	24.831500532103583
2018	24.831500532103583
2019	24.831500532103583
2020	24.831500532103583
2021	24.831500532103583