The complete public-data Zebra Spindle Index dataset — every month since 2011, every component's transformed value and z-score, the calibration table, as-published and latest-revised histories, and the satellite panels (effective tariff rates, capex imports, end markets, industrial electricity) — is free under CC BY 4.0. We ask for an email so we can tell you when a release is revised or the method changes, and so we know who is using it.
The Zebra Coolant-System Activity Pulse is proprietary Zebra Skimmers data and is not included in this dataset. Zebra publishes it on the index page only, as a limited, aggregated, delayed reference signal; /api/pulse-public.json returns the current period and band and nothing more.
| URL | what |
|---|---|
/api/zsi.json | index history (latest-revised + as-published), components, calibration, public series table |
/api/zsi.csv | month, ZSI, component z-scores |
/api/panels.json | satellite series: tariff rates, capex imports, end markets, abrasives, cost, electricity |
/api/pulse-public.json | Zebra Pulse: current period + band only (proprietary; not CC BY) |
Send the key as ?key=…, an X-API-Key header, or Authorization: Bearer …. Responses are cached 5 minutes; the index updates once a month (~the 12th, two months in arrears). No rate limit for reasonable use.
{
"method_version": "2.3",
"meta": {
"latest_month": "2026-08"
},
"index": [
{
"obs_month": "2026-08",
"zsi": 107.65,
"components": {
"C2": {
"raw": 0.08675,
"z": 0.8793,
"w": 0.25
},
"C2b": {
"raw": 0.06761,
"z": 1.509,
"w": 0.075
}
}
}
],
"…": "…"
}| field | meaning |
|---|---|
index[].zsi | 100 + 10 × Σ(weight × z). 100 = calibration-period norm; 10 points = one robust SD. |
index[].components[C].raw | the transformed input (annualized 3m/3m log growth, level change, or YoY log change — see methodology) |
index[].components[C].z | frozen robust z of raw, clipped to ±3 |
index[].components[C].w | fixed weight |
as_published[] | the number shown on each release day — never rewritten |
calibration[] | median, MAD, weight and window per component for the current method version |