FILE INFORMATION FOR NICKEL DATA FILES

     NICKEL4 contains data for all of the 4x4x5x5 cells indexed by
age first employed, year first employed, exposure category, and
time since first employed.


     NICKEL4 has the following format:

          4(X,I2),6X,4(X,I3),4(X,F12.6);   242 records.

     The variables are:

          NICKEL4                       
          -------                      

          AFE                         
          YFE                        
          EXP                       
          TFE                      
          TOTAL PERSONS           
          LUNG CA. DEATHS        
          NASAL CA. DEATHS      
          TOTAL DEATHS         
          PERSON YEARS                
          EXP. LUNG CA. DEATHS       
          EXP. NASAL CA. DEATHS     
          EXP. TOTAL DEATHS        

where
          AFE = age first employed
          YFE = year first employed
          EXP = exposure category
          TFE = time since first employed.

Note - all expected deaths are multiplied by 1000.

     The categories are:

          AFE:    1 = < 20.0
                  2 = 20.0-27.5
                  3 = 27.5-35.0
                  4 = 35.0-85.0

          YFE:    1 = < 1910.0
                  2 = 1910.0-1914.999
                  3 = 1915.0-1919.999
                  4 = 1920.0-1924.999

          EXP:    1 = 0.0
                  2 = 0.5-4.0
                  3 = 4.5-8.0
                  4 = 8.5-12.0
                  5 = 12.5 +

          TFE:    1 = 0.0-19.999
                  2 = 20.0-29.999
                  3 = 30.0-39.999
                  4 = 40.0-49.999
                  5 = 50.0 +