Despite the criticality of tax administration (TA) reforms in enhancing domestic revenue mobilization, few studies have attempted to quantify the revenue impact of such reforms. This paper fills this gap by estimating the revenue yields associated with various tax administration capabilities, based on the International Survey on Tax Administration (ISORA), the Tax Administration Diagnostic Assessment Tool (TADAT), and TA reform episodes datasets (identified by Akitoby et al., 2020). It uses a Hausman-Taylor cross-country panel regression and an event study for specific TA reform episodes. Our results (using the ISORA data) show that an increase in the overall strength of TA from the 40th percentile to the 60th percentile is associated with an increase in tax revenue by 1.8 pp. of GDP (with a 95 percent confidence range of 0.5‒2.6 pp. of GDP). Similarly, the event-study assessment shows that sustained TA reforms led to an increase in tax revenues between 2 to 3 pp. of GDP, in line with the experience in three country cases (Jamaica, Rwanda, and Senegal). Also, the revenue yields are increasing over time to more than 3 pp. of GDP after the 6th year following a comprehensive reform. The analysis also highlights the significant impact of specific measures including: i) strengthening compliance risks management, ii) enhancing public accountability, iii) establishing Large Taxpayer Offices (LTO), iv) strengthening accountability and transparency, and v) enhancing timely filing of tax declarations.

This note outlines the interest of Revenue Administrations (RAs) and National Statistical Offices (NSOs) in the quality of data at their disposal, and how collaboration between these organizations can contribute to improving data quality. The similarities between the data collection and processing steps in revenue administration and in the production of economic statistics underlie meaningful information and data sharing. Mutually beneficial collaboration between RAs and NSOs can be achieved, particularly in efforts to improve the coverage of registers and to update register information; classify economic activity; and analyze joint data to address data shortcomings. Since there are differences in concepts and definitions used in revenue administration and official statistics, dialogue is necessary to ensure the effective use of data from the partner organization. Collaboration can improve the quality of data available to both institutions: for RAs, this can assist in realizing improved taxpayer compliance and revenue mobilization, and for NSOs, tax-administrative data sources may enable expanded coverage of the economy in official statistics and reduce timeframes required for publishing economic time series and national accounts. Together, these outcomes can enhance the policy formulation, planning, and service delivery capability of governments. To that end, this note delineates concrete steps to engender sustainable and meaningful interchange of information and data between the RA and NSO.

This paper presents the results of the International Survey on Revenue Administration (ISORA) deployed during 2016 and covering fiscal years 2014 and 2015. It is made possible by the participation of 135 tax administrations from around the world that provided data.

Assessing how Asia and the Pacific can benefit from stronger tax systems, this comparative analysis drills down into the set-ups and performance of revenue bodies in 41 economies to highlight reform challenges and outline opportunities. Drawing on the results of the International Survey on Revenue Administration (ISORA 2022) survey, it provides background on each economy, details the performance of their revenue bodies, and looks at growing digitalization. The seventh edition in the series, it outlines major trends and sets out ways governments and officials can reform their revenue bodies to build more effective and efficient tax systems.

This report is the 5th edition of ADB’s A Comparative Analysis of Tax Administration in Asia and the Pacific. It provides internationally comparative data on aspects of tax systems and their administration in 38 economies and detailed analysis of the comparative results across the region, aiming to assist the revenue bodies to improve their performance by providing opportunities to benchmark their administration against similar economies in the region. The comparable data and analysis are based largely on the 2020 round of the International Survey on Revenue Administration, for the 2018 and 2019 fiscal years.

For ADB members in Asia and the Pacific, stronger tax systems are now more important than ever—to boost revenues enabling recovery from the economic shocks of COVID-19, and to reinforce implementation of Sustainable Development Goals. Using comparative data up to the fiscal year 2020, and drawing from the International Survey on Revenue Administration (ISORA 2021), this sixth edition in our series analyzes the administrative setups and performance of revenue bodies in 40 economies across the region—to help governments and officials identify promising options for building more efficient, inclusive tax systems.

An engaging and enlightening account of taxation told through lively, dramatic, and sometimes ludicrous stories drawn from around the world and across the ages Governments have always struggled to tax in ways that are effective and tolerably fair. Sometimes they fail grotesquely, as when, in 1898, the British ignited a rebellion in Sierra Leone by imposing a tax on huts—and, in repressing it, ended up burning the very huts they intended to tax. Sometimes they succeed astonishingly, as when, in eighteenth-century Britain, a cut in the tax on tea massively increased revenue. In this entertaining book, two leading authorities on taxation, Michael Keen and Joel Slemrod, provide a fascinating and informative tour through these and many other episodes in tax history, both preposterous and dramatic—from the plundering described by Herodotus and an Incan tax payable in lice to the (misremembered) Boston Tea Party and the scandals of the Panama Papers. Along the way, readers meet a colorful cast of tax rascals, and even a few tax heroes. While it is hard to fathom the inspiration behind such taxes as one on ships that tended to make them sink, Keen and Slemrod show that yesterday’s tax systems have more in common with ours than we may think. Georgian England’s window tax now seems quaint, but was an ingenious way of judging wealth unobtrusively. And Tsar Peter the Great’s tax on beards aimed to induce the nobility to shave, much like today’s carbon taxes aim to slow global warming. Rebellion, Rascals, and Revenue is a surprising and one-of-a-kind account of how history illuminates the perennial challenges and timeless principles of taxation—and how the past holds clues to solving the tax problems of today.

This report is the tenth edition of the OECD's Tax Administration Series. It provides internationally comparative data on global trends in tax administrations across 58 advanced and emerging economies.

It is generally difficult to measure revenue not collected due to noncompliance, but a growing number of countries now regularly produce and publish estimated revenue losses. Good tax gap analysis enables the detection of changes in taxpayer behavior by consistent estimates over time. This Technical Note sets out the theoretical concepts for personal income tax (PIT) gap estimation, the different measurement approaches available, and their implications for the scope and presentation of statistics. The note also focuses on the practical steps for measuring the PIT gap by establishing a random audit program to collect data, and how to scale findings from the sample to the population.