For those seeking economic data on oil exports by country, the best sources include national departments of statistics and specialized organizations like the U.S. Energy Information Administration (EIA), which provides comprehensive data on energy markets. Users can also refer to the BP Statistical Review of World Energy for detailed insights into oil trade movements. While Mathematica's "CountryData" function lacks this specific functionality, manually aggregating data from these sources can yield the necessary information. The discussion emphasizes the complexity of oil trade, noting that oil often changes hands multiple times before reaching its final destination, unless specified by trade agreements.