PIT audit yield relative to PIT collections

Notes:

Each line shows the median audit-yield ratio for respondent jurisdictions in the GNI group, per year. The ratio for each jurisdiction-year is the value of additional PIT assessments raised from audits and verification actions (ISORA A.83, including penalties and interest) divided by PIT net revenue collected in that year (ISORA A.6). Both are reported in thousands of local currency, so the ratio is unit-free and comparable across jurisdictions.

Interpretation: a ratio of 2% means audits added uplift equivalent to roughly 2% of baseline PIT collection. Higher values can reflect either stronger audit selection and yield or a larger compliance gap being closed — the ratio alone does not distinguish those two causes. Values are small, so they are displayed to two decimal places.

Jurisdictions are included in each year’s median only when both figures are reported and PIT revenue is positive. ISORA does not collect a PIT-specific count of audits or audits finding a tax adjustment, so a classic ‘audit hit rate’ cannot be built at the PIT level from this survey.

The faint grey lines behind the medians are the individual reporting jurisdictions — where they bunch, the overlapping lines read darker, so the medians can be seen against the spread they summarise. When a jurisdiction is highlighted, the chart focuses on its GNI group: that group’s members and median stay, and the jurisdiction’s own ratio series is overlaid as a dashed red line. The ratio has no natural ceiling, so the y-axis is scaled to the tier medians; lines above that ceiling are clipped for readability.

Source: ISORA Derived Tables A.6, A.83 (PIT net revenue; additional assessments from audits).