For each tracked vendor we compute a per-vendor Nerf Index (0–100) - a recency-weighted sum of event scores under a 180-day exponential half-life, squashed through a logistic so the worst offenders cluster near 100 instead of running away.

1// per-event weight under 180-day half-life decay2weight(event) = 2 ^ ( -age_days / 180 )3 4// market index = count-weighted mean across active vendors5market = Σ ( vendor_index_i × √receipts_i ) / Σ √receipts_i

We weight by sqrt(receiptCount) so loud vendors don't dominate but quiet ones don't pad the average. Vendors with zero receipts are excluded.

The 30-day series re-computes the market index at each day using only receipts published on or before that date - so the line shows how the market actually evolved, not today's snapshot projected backwards. Full event-scoring rubric: /methodology.

DATA & FEEDS MIT-licensed · CORS-open

JSONlive feed

Index feed

Single-number index + 30-day series + per-vendor breakdown. Stable URL. Ideal for dashboards & agents.

gotnerfed.com/data/nerf-index.json→

DATASET41 receipts

Full receipts corpus

Every receipt the index aggregates over. JSON + CSV + vendor index. Updated within an hour of publish.

gotnerfed.com/data→

CITATIONGotNerfed Market Nerf Index (https://gotnerfed.com/nerf-index). Updated 2026-09-24. MIT license.