Year,US_land_kmt,US_discd_kmt,Other_land_kmt
1935,6.00,2.40,0.00
1936,6.80,2.70,0.00
1937,7.60,3.00,0.00
1938,7.70,3.10,0.00
1939,9.50,3.80,0.00
1940,14.20,5.70,0.00
1941,19.30,7.70,0.00
1942,28.40,9.90,0.00
1943,18.00,7.30,0.00
1944,10.60,4.80,0.00
1945,10.40,4.20,0.00
1946,10.80,4.40,0.00
1947,12.10,4.90,0.00
1948,9.90,4.00,0.00
1949,4.90,1.90,0.00
1950,4.90,1.90,0.00
1951,2.90,1.10,0.00
1952,3.20,1.20,0.00
1953,2.30,0.80,0.00
1954,1.70,0.60,0.00
1955,2.50,0.90,0.00
1956,4.10,1.40,0.00
1957,6.20,2.20,0.00
1958,9.50,3.60,0.00
1959,8.20,3.10,0.00
1960,8.80,3.20,0.00
1961,13.00,4.70,0.00
1962,13.50,5.30,0.00
1963,22.60,5.40,0.20
1964,21.81,9.50,0.00
1965,22.52,7.00,1.40
1966,22.54,5.30,0.70
1967,25.14,7.70,2.80
1968,25.37,6.30,3.50
1969,23.69,2.40,18.28
1970,21.35,4.50,2.62
1971,15.87,2.20,1.26
1972,17.57,1.80,3.12
1973,12.44,1.71,0.40
1974,8.28,8.69,0.12
1975,3.83,1.90,0.00
1976,1.85,1.58,0.00
1977,3.34,1.89,0.00
1978,3.06,5.03,0.00
1979,5.45,4.43,0.00
1980,6.30,1.72,0.00
1981,5.40,1.21,0.00
1982,10.73,5.04,0.00
1983,18.50,3.71,0.00
1984,10.10,1.12,0.00
1985,3.60,1.22,0.00
1986,3.55,1.07,0.00
1987,1.77,0.88,0.00
1988,0.99,1.79,0.00
1989,2.90,5.45,0.00
1990,8.24,9.68,0.00
1991,4.11,2.32,0.00
1992,1.64,1.06,0.00
1993,0.67,0.10,0.00
1994,0.39,0.26,0.00
1995,0.19,0.09,0.00
1996,0.46,0.09,0.00
1997,0.78,0.04,0.00
1998,0.58,0.13,0.00
1999,1.16,0.15,0.00
2000,0.97,0.05,0.00
2001,1.05,0.07,0.00
2002,0.75,0.13,0.00
2003,0.42,0.08,0.00
2004,0.17,0.13,0.00
2005,0.10,,0.00