Overview

• Drawing on data from roughly 15,000 fields, the IEA finds average post‑peak declines of about 5.6% for conventional oil and 6.8% for gas, with shale output falling by more than 35% in the first year without reinvestment.
• Nearly 90% of upstream spending since 2019 has been used to offset declines, and investment near $570 billion in 2025 would only sustain modest production growth.
• Stopping upstream investment would cut oil supply by around 5.5 million barrels per day each year and reduce gas by about 270 bcm, heightening risks to market stability and energy security.
• Absent significant demand reductions, maintaining today’s output through 2050 would require more than 45 million barrels per day of oil and nearly 2,000 bcm of gas from new conventional projects.
• The report’s conclusions drew immediate pushback, with the U.S. administration criticizing the IEA and OPEC calling it a U‑turn, as the agency also warns supply would concentrate further in the Middle East and Russia if investment lags.