Non-Linear Costs and Returns to Scale: Some Disaggregate Results

The annual time-series( 1975-92) data used for estimation purposes cover the 58 biggest 'firms' (companies or corporations) which trade on

75 See Bairam (1994) for proofs and implicit assumptions.

the New York Stock Exchange.76 All the data used (except the price index) were from the Standard and Poor’s Computstat data base and were all in 1973 prices.