Year,Spring_kg_tow,Fall_kg_tow
1963,,6.3100
1964,,4.1400
1965,,6.8600
1966,,7.6700
1967,,3.6400
1968,1.7400,4.5400
1969,5.0900,13.0900
1970,11.8600,12.8200
1971,5.1400,12.1000
1972,12.6600,13.1000
1973,12.2200,13.4600
1974,13.9900,11.0000
1975,11.2200,7.2300
1976,17.0100,10.5600
1977,11.0100,13.7400
1978,6.1400,12.5400
1979,4.9700,10.3100
1980,13.9600,16.6600
1981,19.9200,12.1600
1982,8.9100,2.1100
1983,3.1200,10.7900
1984,4.1700,8.2300
1985,5.3800,9.7400
1986,5.6100,11.5600
1987,6.4400,9.6200
1988,3.6900,9.8800
1989,3.2200,9.2300
1990,18.3700,10.5800
1991,6.1400,12.2000
1992,7.1100,11.2400
1993,6.8400,11.6600
1994,3.1700,7.0200
1995,4.0200,8.2000
1996,3.0700,6.3500
1997,0.8900,4.5500
1997,1.0900,4.2700
1999,2.9700,3.4400
2000,3.3300,6.7200
2001,5.1800,7.9700
2002,6.3200,6.7300
2003,5.7300,4.9100
2004,5.1900,3.7200
2005,5.5200,3.5880
2006,1.4640,