The research paper linked by the parent comment is using Gross Operating Surplus and EBITDA metrics: Gross operating surplus differs from profits shown in company accounts for several reasons. Only a subset of total costs are subtracted from gross output to calculate the gross operating surplus. Essentially it is gross output less the cost of intermediate goods and services to give gross value added, and less compensation of employees and taxes and subsidies on production and imports.

There are obvious financial cost increases that have happened which are falsely represented as 'profit' in this analysis.