Documentation

Data

Debugging Fairfax uses publicly available Fairfax County budget documents. All data used by the tool is published in an open repository so anyone can inspect, verify, or reuse it.

Source Documents

The analysis is derived from official Fairfax County budget publications and supporting financial tables.

  • Fairfax County Adopted Budget FY2026
  • Fairfax County Proposed Budget FY2027
  • Departmental appropriation summaries
  • Real estate tax revenue projections

Data Processing

Budget data is extracted from county reports and normalized into structured tables that allow comparisons between fiscal years. Spending categories are grouped into major functional areas to make the budget easier to understand for residents.

These normalized datasets are then used by the Debugging Fairfax tool to estimate budget context and category-level allocation changes. The tax bill change estimate itself uses only assessment and tax rate inputs.

Open Data Repository

All datasets used by this project are published publicly. The repository includes the source data, structured datasets used by the tool, and a full history of changes as the county budget evolves.

GitHub repository:

github.com/Debugging-Fairfax/debugging-fairfax-data

The repository provides revision history so users can see exactly when data changes were made and reproduce the analysis.

Data Updates

The datasets used by Debugging Fairfax are updated whenever Fairfax County publishes new or revised budget documents. Updates typically occur during the annual budget cycle and when the county releases revised financial tables.

Every change to the data is recorded in the public GitHub repository so residents can see exactly when updates were made and what changed.

View the full update history:

github.com/Debugging-Fairfax/debugging-fairfax-data/commits

All historical revisions remain permanently available.

Transparency

Debugging Fairfax is an independent civic data project. The goal is to make government budget information easier for residents to understand. All calculations are based on publicly available data and can be independently verified.