Badi H. Baltagi, James M. Griffin, and Sharada R.Vadali. 
"Excess Capacity: A Permanent Characteristic of U.S. Airlines, "
Journal of Applied Econometrics, Vol. 13, No. 5, 1998, pp. 645-657.

All data are in the file costfn.dat, a file in DOS format that is zipped
in bgv.zip. 

ORGANIZATION OF DATA IN THE COSTFN.DAT FILE.
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TOTAL NUMBER OF OBSERVATIONS IN THE DATASET=268;
UNBALANCED PANEL DATA OF 23 AIRLINES FOR THE PERIOD 1971-86;
NUMBER OF VARIABLES PER AIRLINE PER YEAR (INCLUDING NAME
AND YEAR)=13;
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ORDER IN WHICH VARIABLES SHOULD BE READ:
YEAR VC Y K PL PM PF PK LS MS RS STAGE NAME;
ALL VARIABLES ARE NUMERIC EXCEPT NAME. 
NAME HAS A CHARACTER FORMAT.  EXAMPLE: THE
FIRST TWO LINES OF THE DATASET CONTAIN INFORMATION
FOR THE YEAR 1971, FOR AL-- ALLEGHENY AIRLINES.
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NOTES 
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Y= OUTPUT (multilateral index of seat miles actually flown);
"VC=VARIABLE COST (sum of labor, fuel, material costs);"
K=CAPITAL STOCK;  
PL=PRICE OF LABOR; PM=PRICE OF MATERIALS; PF=PRICE OF FUEL;
PK=PRICE OF CAPITAL;
LS=LABOR COSTS/ VARIABLE COSTS (labor share in variable costs);
MS=MATERIAL COSTS/VARIABLE COSTS (material share in variable costs);
RS=REVENUE SHARE VARIABLE=(REVENUE/VARIABLE COSTS);
STAGE=STAGE LENGTH MEASURED AS AVERGE LENGTH IN MILES OF A FIRM'S
      FLIGHT; 
NAME=NAME OF THE AIRLINE;
YEAR=YEAR;
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DATA SOURCES:
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Many of the variables noted above are translog multilateral indices.
The primary data source for the variables are the DOT Form 41 
"Reports (Schedules B1, P1, P3, P5, P6, P7, P8, P10, T2 and T3);"
The Code of Federal Regulations (Part 241) provides all the reporting 
requirements.
PM=Material price index based on U.S. aggregate producer price
index for supplies.
PE=Fuel price index based on cost per gallon.
PL=Labor multilateral wage index of average compensation per full-time
equivalent employee (including benefits and payroll taxes) based on
five occupational categories.
Revenue data, needed to create the revenue share variable, is obtained
from financial statements of the companies. 
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