# Data Dictionary - Hyperliquid Perp Book Asymmetry - impact skew & spread, hourly Parquet

**Units:** vary by `metric` - read the per-row `unit` column (overall: bps).  Times are UTC.

| column | type | description |
|---|---|---|
| `zone` | str | Coin (perp ticker) |
| `ts` | timestamp (UTC) | Hour (bar start) |
| `metric` | str | impact_skew_bps or spread_bps |
| `value` | float | Metric value in basis points |
| `unit` | str | Unit (bps) |
| `res_min` | int | Native resolution in minutes (60 = hourly) |

*Source: Hyperliquid (on-chain perpetual DEX) - public asset-context data.*