UNCTAD ranks the largest non-financial TNCs by their foreign assets and presents data on assets, sales and employment in three separate lists: the 100 largest worldwide, the largest 100 from developing countries, and the largest 10 from the economies in transition of Eastern Europe and the CIS.

Financial firms are included in a separate list, the 50 largest worldwide, because of the different economic functions of assets of financial firms and the non-availability of relevant data on sales and employment. UNCTAD ranks the firms according to a Spread Index which takes into account the number of foreign affiliates and the number of host countries.

The same ranking, together with an analysis of the relevance of these TNCs in the world economy, is included in the various issues of the World Investment Report.