The International Survey on Revenue Administration (ISORA) collects data annually on tax administrations through an on-line survey completed by tax administrations. ISORA includes data on tax collections, tax administration operations, expenditures, and other structural characteristics of tax administrations. ISORA is the collaborative product of five international organizations: the Asian Development Bank (ADB), the Inter-American Center of Tax Administrations (CIAT); the International Monetary Fund (IMF); the Intra-European Organisation of Tax Administrations (IOTA); and the Organisation for Economic Co-operation and Development (OECD).