In 2004, the Fiscal Reform I Project published a seminal paper on benchmarking tax systems. This paper proposed a framework for analysis and a set of international comparator indicators that can be used in the diagnosis of tax system ills. The indicators relate to tax structure, revenue performance, compliance, tax administration organization, staffing, systems, legal framework, and other factors that relate to how a tax system operates. This paper was developed based on many years of prior research and test application. The benchmarking approach can serve as a tool in diagnosing tax systems, comparing tax systems, developing interventions to improve tax systems, and setting goals and targets for tax system modernization, raising compliance, reducing evasion, and improving overall system performance.

Building on this conceptual tool, the Fiscal Reform Project developed an international comparator database , complete with comprehensive source notes. Most of the data in this original database date from 2001 to 2005, though some data are from the 1990s.

The benchmarking methodology has been applied in a number of cases. In some cases the methodology was applied even before the basic paper was published, such as in Guatemala (1995), El Salvador (1994), and Tanzania (1998). The methodology was applied again twice in Guatemala, in 2001 and subsequently in 2004.Since 2005, the methodology has been applied in a number of countries around the world, including twice in El Salvador(2005 and 2006), once in Moldova (2008), and partially in Bosnia and Herzegovina, Croatia, Central Asia, and Vietnam.

The benchmarking data now form the core of the Fiscal Reform II Project's new Collecting Taxes data system. Collecting Taxes features more than two dozen structural and performance indicators across approximately 200 countries and teritories.  The new system features broader coverage of benchmarking data and expands the number of indicators presented, based on most recent estimates for each economy. The project now updates the database annually.

Benchmarking Tax Systems (.pdf file)
A methodology for assessing tax system structure and performance

Benchmarking Database - 2004 (.xls file)
The complete 2004 database; see www.collectingtaxes.net for database updates 

Technical Notes to the Benchmarking Database - 2004 (.doc file)
Source notes and references for the 2004 database