The Calcbench report for Q3 2015 highlights a 6.25% year-over-year decline in corporate revenues, primarily attributed to significant drops in the petroleum sector. Capital expenditures fell by 9% but small firms saw a slight increase of 2.1%, while operating expenses rose by 7.7%. Despite the overall downturn, top firms controlled a growing percentage of U.S. revenue, indicating ongoing consolidation in the market.