ATO logo

Reliability of the wine equalisation tax gap estimate

How we make sure the wine equalisation tax (WET) gap estimate is reliable.

Published 3 November 2025

We sought feedback and advice from external experts on the appropriateness and robustness of our new estimation method based on a multi-stage regression approach. Poisson pseudo maximum likelihood (PPML) regression better fits the data and enables us to use a richer dataset, improving the reliability of the estimates. They have supported our revised reliability rating of high with a score of 21.

Figure 3: Reliability rating scale from very low to very high − WET gap

The reliability rating of high for the current WET gap estimate. The WET gap estimate itself is rated at 21. The rating scale includes very low (1-10), low (11-15), medium (16-20), high (21-25), very high (26-30).

 

QC105766