Eni adjusted net profit: €0.56 billion for the quarter, down by 27% q-o-q (down by 24% excluding IFRS 16 accounting effects). €1.55 billion in the first half, down by 11% (down by 8% excluding IFRS 16 accounting effects).

Net income for 43 U.S. oil producers totaled $28 billion in 2018, a five-year high. Based on net income, 2018 was the most profitable year for these U.S. oil producers since 2013, despite crude oil prices that were lower in 2018 than in 2013 on an annual average basis.

BP - Underlying replacement cost profit for full year 2018 was $12.7 billion, more than double that reported for 2017. The fourth quarter result was $3.5 billion, driven by the strong operating performance across all business segments.

The decline in earnings was driven largely by the decline in crack spreads (the price difference between crude oil and petroleum products) in the second quarter. In addition to changes in crack spreads, which serve as an indicator of refinery profits, earnings per barrel reflect transportation costs and other operating expenses. Also, refiners use different crude oil blends and produce different yields of refined products, which changes the per barrel earnings among refiners.

Brent crude oil prices averaged at the lowest level since 2004, significantly reducing profits and cash flow for energy companies.