Methodology & source manifest
Everything on the Department of Homeland Security monitor derives from public records — the DHS Budget-in-Brief, OMB's Historical Tables, the USAspending API, and reachable DHS OIG and GAO oversight documents. This page is the audit trail: method, sources, validation, and every flag.
Method
Net vs. gross discretionary vs. the DRF
The Budget-in-Brief builds Total Budget Authority → less mandatory/fee/trust → Gross Discretionary → less offsetting fees → less the FEMA Disaster Relief Fund major-disaster allocation → Net Discretionary. This monitor leads with NET discretionary — the post-offset figure appropriations actually fund — and keeps Gross (which adds back fee / offsetting-collection accounts) and Total Budget Authority (which adds mandatory / trust accounts such as the USCIS Immigration Examinations Fee Account and FEMA's DRF and flood-insurance accounts) as clearly-labeled separate frames. The $28.4B Disaster Relief Fund major-disaster line is reported on its own and never folded into the net headline.
The reconciliation gap
The discretionary appropriation accounts keyed for each organization sum, to the dollar, to that organization's published Net Discretionary subtotal — asserted at build time, per fiscal year. For the FY2027 request the sum of all twelve organizations ties exactly to the published department Net Discretionary topline. For the FY2025 and FY2026 continuing-resolution columns, a small, consistent department-level adjustment (the Disaster Relief Fund major-disaster, CHIMP, and rescission roll-ups applied only at the department total) separates the two; that gap is reconciled and flagged below, never absorbed into a component or appropriation.
Source documents & validation ledger
The history layer is shown in nominal dollars only — OMB Historical Table 5.2 publishes no constant-dollar basis for DHS, and no deflator is synthesized. DHS began operations in 2003, so the budget-authority series begins there; pre-2003 back-years do not exist and are not fabricated.