International Energy Agency:

How the Agency Prepares Its World Oil Market Statistics

RCED-99-142: Published: May 7, 1999. Publicly Released: Jun 7, 1999.

Additional Materials:


Victor S. Rezendes
(202) 512-6082


Office of Public Affairs
(202) 512-4800

Pursuant to a congressional request, GAO provided information on: (1) how the International Energy Agency (IEA) prepares its world oil market statistics; and (2) what accounted for the missing barrels in IEA's historical world oil market statistics in 1998.

GAO noted that: (1) IEA uses a bottom-up approach to prepare its historical and projected oil market statistics; (2) under this approach, IEA constructs historical and projected oil market statistics for individual countries and adds them together to develop world totals; (3) for its historical statistics, IEA uses questionnaires and information from various other sources--such as national governments, international organizations, and oil companies--to obtain the data; (4) according to oil market experts GAO spoke with, IEA's historical statistics are the best available data on world oil supply, demand, and stocks; (5) for its projected statistics, IEA uses its own analysis and judgments based on a number of factors that influence world oil supply and demand; (6) these factors include, for example, for supply, changes in oil production rates for 400 oil fields and, for demand, changes in the structure of the economy and energy demand of each country; (7) IEA keeps the price of oil constant throughout the projection period because the agency has a policy of not forecasting oil price; (8) missing barrels are accounted for by two factors: (a) limitations in the statistics on oil supply, demand, and stocks reported to IEA, such as preliminary data that are subject to future revision; and (b) actual oil held in stocks but not reported as part of IEA's official oil stock statistics; (9) although highlighted by IEA in April 1998, missing barrels are not new, having occurred in 24 of the last 26 years; (10) in 1998, IEA estimated world oil supply at 75.3 million barrels per day, world oil demand at 73.7 million barrels per day, and increases in Organization for Economic Cooperation and Development oil stocks at 0.4 million barrels per day; and (11) the remaining 1.2 million barrels per day (or 438 million barrels for the year) are the estimated missing barrels for 1998, and represent about 1.6 percent of the approximately 75 million barrels traded in the world oil market every day.

Oct 29, 2020

Oct 15, 2020

Jul 24, 2020

Jun 24, 2020

Jun 9, 2020

May 13, 2020

May 12, 2020

Apr 29, 2020

  • energy icon, source: Art Explosion

    Priority Open Recommendations:

    Department of Energy
    GAO-20-285PR: Published: Apr 22, 2020. Publicly Released: Apr 29, 2020.

Apr 17, 2020

Mar 11, 2020

Looking for more? Browse all our products here