Methodology: NFIP flood policies in force
Every figure carrying this label on a county page is computed exactly as described below, from public government data. Nothing is estimated or editorialized.
| What it measures | NFIP flood policies currently in force |
|---|---|
| Unit | policies |
| Source dataset | FEMA — OpenFEMA NFIP Redacted Policies v2 |
| Data version / accessed | through 2026-05 (cube build 2026-07-21b, generated 2026-07-21) |
| Exact source fields | policyEffectiveDate, policyTerminationDate, policyCount, countyCode |
| Formula | SUM(policy_count) WHERE effective<=build_date<termination per county (build_date pinned in meta_cube) |
| Predicates / filters | SUM(policyCount) over policies whose effective date <= the build date and whose termination date is null or after it — a true point-in-time STOCK, not an annual flow. |
| Date semantics | STOCK as of build_date — not an annual figure |
| Window boundaries | point-in-time stock as of the build date 2026-07-21 (a stock, not a date window) |
| Rounding | none (integer count) |
| Suppression rule | tile hidden below min_n=10 |
| Minimum sample (min_n) | 10 |
| Geography | US county (FIPS) |
Internal build query
This query runs against our internal data cube (private cube_*/fct_* tables built from the public sources below). It is exact but not runnable by a reader — use the public reproduction recipe that follows.
SELECT SUM(policy_count)
FROM fct_nfip_policy
WHERE county_fips = :fips
AND policy_effective_date <= :build_date
AND (policy_termination_date IS NULL
OR policy_termination_date > :build_date);Reproduce from the public source
This recomputes the figure from the raw public dataset. Public data is live and may run ahead of our snapshot (see the data version above); numbers can differ by rows added since our ingest vintage.
OpenFEMA FimaNfipPolicies v2 — fema.gov/api/open/v2:
$filter = countyCode eq '<fips>' and policyEffectiveDate le '<build-date>'
and (policyTerminationDate eq null or policyTerminationDate gt
'<build-date>')
SUM(policyCount) over the result (a point-in-time stock).Worked example: Harris County: 190,470 NFIP policies in force as of the build date.
Change log
2026-07-21 (r3) — window boundaries corrected (no windowed metric reads "not windowed"); LIMIT/ordering/geography/status predicates documented; the query relabeled the internal build query and paired with a public raw-source reproduction recipe.
2026-07-21 — record published with source URL, exact fields, predicates, window boundaries, rounding, suppression, and a worked example. Prior records disclosed a formula only.
Corrections
Spotted an error? Corrections: support@countyguard.com. We publish the fix and note it in this change log.
Independent professional (adjuster/restoration) review of the guidance built on these figures is pending and blocks release (D2). This record documents the data method only; it is not insurance, legal, or engineering advice.