File name:      XON.DAT. Scale factor=      10                                  
51,39,4,0-.335,12
06,15,1979,62.500
09,15,1979,37.701
12,15,1979,639.386
03,15,1980,70.923
06,15,1980,139.600
09,15,1980,139.200
12,15,1980,760.339
03,15,1981,38.063
06,15,1981,-26.800
09,15,1981,28.300
12,15,1981,1161.933
03,15,1982,157.863
06,15,1982,149.300
09,15,1982,182.100
12,15,1982,1254.022
03,15,1983,214.194
06,15,1983,251.500
09,15,1983,195.800
12,15,1983,1207.363
03,15,1984,201.797
06,15,1984,249.900
09,15,1984,182.700
12,15,1984,1136.600
03,15,1985,167.500
06,15,1985,311.200
09,15,1985,311.900
12,15,1985,1329.800
03,15,1986,83.300
06,15,1986,189.200
09,15,1986,166.900
12,15,1986,1290.300
03,15,1987,129.700
06,15,1987,338.000
09,15,1987,142.000
12,15,1987,1429.900
03,15,1988,233.200
06,15,1988,240.500
09,15,1988,210.600
12,15,1988,1453.600
03,15,1989,187.799
06,15,1989,194.100
09,15,1989,149.000
12,15,1989,1729.100
03,15,1990,141.500
06,15,1990,245.900
09,15,1990,228.000
12,15,1990,1640.600
03,15,1991,198.900
06,15,1991,202.600
09,15,1991,273.400
12,15,1991,1485.800