Cross-Platform
Spread History
Use spread history to chart how cross-venue dislocations change over time.
GET
/api/v2/spreads/historyGet spread history
Returns historical spread data points for an event slug and outcome key over a time range.
Request
curl 'https://api.thepredictionmarkets.com/api/v2/spreads/history?event_slug=top-artist-on-spotify-us-in-2026&outcome_key=text:drake&range=1w' \
-H 'X-API-Key: YOUR_TPM_API_KEY'Response
{
"event_slug": "top-artist-on-spotify-us-in-2026",
"outcome_key": "text:drake",
"range": "1w",
"data": [
{ "timestamp": "2026-04-16T00:00:00", "spread_bps": 5200, "price_a": 0.12, "price_b": 0.64 },
{ "timestamp": "2026-04-17T00:00:00", "spread_bps": 6100, "price_a": 0.11, "price_b": 0.72 }
]
}Query Parameters
| Name | Type | Required | Default | Example | Description |
|---|---|---|---|---|---|
| event_slug | string | Yes | - | top-artist-on-spotify-us-in-2026 | Event slug. |
| outcome_key | string | Yes | - | text:drake | Outcome key from spread response. |
| range | 1d | 1w | 1m | all | No | 1w | 1w | Preset history range. |
Response Fields
| Field | Type | Example | Description |
|---|---|---|---|
| data | object[] | - | Time-series points with timestamp, spread_bps, price_a, and price_b. |
| data.timestamp | string | - | ISO timestamp for the data point. |
| data.spread_bps | number | - | Spread in basis points at that time. |
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