2017年-IMF国际货币组织全球_The_Revenue_Administration–Gap_Analysis_Program_Model_and_Methodology_for_Value_32页_2mb

Summary of the Revenue Administration—Gap Analysis Program: Model and Methodology for Value-Added Tax Gap Estimation

Core Content

This technical note and manual from the IMF Fiscal Affairs Department outlines the Revenue Administration—Gap Analysis Program (RA-GAP), which provides a top-down methodology for estimating the Value-Added Tax (VAT) gap. The VAT gap is defined as the difference between potential VAT revenue (based on economic activity) and actual VAT revenue (collected by the tax administration). It further breaks down the VAT gap into two components: the compliance gap (due to noncompliance and tax evasion) and the policy gap (due to tax reliefs and exemptions).

The RA-GAP model is designed to offer a more detailed and accurate assessment of the VAT gap by disaggregating it by sector, which allows for a better understanding of the sources of revenue loss and helps in improving tax compliance strategies.

Main Approaches to VAT Gap Estimation

There are three main approaches to estimating VAT noncompliance:

• Top-down approach: Compares estimated potential revenue (based on economic data) with actual revenue (from tax returns). It provides a comprehensive view of the overall tax gap but does not identify specific compliance behaviors.
• Bottom-up approach: Uses audit samples or compliance risk analysis to estimate the impact of specific noncompliance behaviors. It is more costly and covers only certain aspects of the tax gap.
• Econometric techniques: Involve statistical models like frontier analysis and time series analysis. These are more complex and less interpretable from a compliance perspective, so they are not recommended for direct tax gap estimation.

The RA-GAP methodology focuses on the top-down approach, offering distinct advantages:

• It breaks the VAT gap into its components by sector and administrative function.
• It aligns with the credit-invoice VAT system, which is the most common structure.
• It uses an accruals-based approach, enabling better alignment between economic activity data and revenue collection.

Key Components of the RA-GAP Model

A. Potential VAT Revenue

The RA-GAP model estimates potential VAT revenue by applying the VAT policy framework to a value-added model of the economy. This model is based on national accounts data, particularly supply-use or input-output tables.

The formula for potential VAT revenue is:

$$
P V = \sum_ {s} \left(P V m ^ {s} + P V o ^ {s} - P V i ^ {s}\right)
$$

Where:

• $PV$ = Total potential VAT revenue
• $PVm^s$ = Potential VAT on imports of sector $s$
• $PVo^s$ = Potential VAT on output of sector $s$
• $PVi^s$ = Potential VAT credits for inputs of sector $s$

1. Adjustments for X and M

• Exports and imports in national accounts are defined differently from their treatment under a VAT.
• Under a destination-based VAT, domestic consumption by nonresidents is taxable, while residents’ consumption abroad is not.
• Therefore, adjustments are made to reflect this difference in the model.

2. Weighted Average Statutory Rate for Trade Margins

• For the retail and wholesale sectors, the model calculates a weighted average VAT rate based on the value of trade margins and the VAT rates applied to different commodities.
• This ensures that the model accounts for the different VAT rates applicable to various products.

3. Accommodating Policy Complexities

• The model accounts for business-to-business (B2B) exemptions and special rates.
• It also addresses business-to-consumer (B2C) treatments, such as reduced rates for certain groups.

B. Actual VAT Revenue

Actual VAT revenue is calculated based on the net VAT for each taxpayer, which is the difference between the VAT due on outputs and the VAT creditable on inputs.

The formula is:

$$
A V ^ {s} = \sum_ {t \in s} \left(V m ^ {t} + V o ^ {t} - V i ^ {t}\right)
$$

Where:

• $AV^s$ = Actual VAT for sector $s$
• $Vm^t$ = VAT on imports for taxpayer $t$
• $Vo^t$ = VAT due on output for taxpayer $t$
• $Vi^t$ = Creditable VAT on inputs for taxpayer $t$

Actual VAT can also be re-expressed using transactions and assessments data, depending on the measurement method used.

C. Measuring and Reporting the Gap

The tax gap is calculated as:

$$
\text{Tax Gap} = RPR - AR
$$

Where:

• $RPR$ = Reference Potential Revenue (based on a standard VAT policy)
• $AR$ = Actual Revenue (collected by the tax administration)

The compliance gap is calculated as:

$$
\text{Compliance Gap} = CPR - AR
$$

Where:

• $CPR$ = Current Potential Revenue (based on the current VAT policy)

The policy gap is the difference between $RPR$ and $CPR$, or equivalently, the tax gap minus the compliance gap.

How the VAT Gap Can Improve Compliance

The RA-GAP methodology provides valuable insights for improving tax compliance by:

• Breaking down the tax gap into its components, helping tax administrators understand where revenue losses are occurring.
• Tracking changes in the gap over time, which can inform policy decisions and the effectiveness of compliance measures.
• Supporting taxpayer compliance management by identifying specific areas of noncompliance and policy-related revenue losses.

Key Information

• The RA-GAP model uses national accounts data and tax administration data.
• It allows for sector-level analysis, which is critical for targeted policy improvements.
• The compliance gap reflects losses due to noncompliance and evasion.
• The policy gap reflects the impact of tax reliefs and exemptions.
• The model accounts for statistical and tax treatment differences, such as how imports and exports are defined.
• It also incorporates policy variables like $r^s$, $\tau_c$, and $\eta_c^s$, which represent:
  • $r^s$: Proportion of value-added in a sector that is produced by VAT-registered entities.
  • $\tau_c$: VAT rate for a commodity.
  • $\eta_c^s$: Proportion of input tax credits denied for a particular commodity in a sector.

Conclusion

The RA-GAP methodology offers a robust, comprehensive, and sector-specific approach to estimating the VAT gap. By aligning with the credit-invoice VAT system and using an accruals-based model, it provides a more accurate picture of tax compliance and policy impacts. The approach is particularly useful for tax administrations and policymakers seeking to improve revenue collection and understand the drivers of noncompliance.