Spread · depth · traded volume · contract state
6Z Liquidity Map: Build a Timestamped Market-Quality Record
A price can be a busy two-sided market on one date and a thin waypoint on another. A visible volume shelf can migrate when the active contract changes, disappear after an event, or look deep until an order reaches the queue. A useful 6Z liquidity map is therefore a dated measurement object—not a permanent set of “institutional zones.”
- Quoted
- Spread + depth
- Traded
- Volume + prints
- Experienced
- Fills + slippage
- Permanent zones
- Not claimed
A map needs more than prints
Separate Quoted, Traded and Experienced Liquidity
Each layer answers a different question. Quoted liquidity describes displayed opportunity; traded liquidity describes completed transactions; experienced liquidity describes what a defined order policy actually received. None can safely stand in for the others.
| Layer | Minimum fields | Useful outputs | Boundary |
|---|---|---|---|
| Quotes | Sequenced bid, ask, quantities, timestamp | Time-weighted spread, depth by distance, quote age | Displayed size can cancel |
| Trades | Price, quantity, time, correction status | Volume distribution, trade count, size distribution | A print does not reveal resting queues |
| Orders | Decision, submit, acknowledge, fill and cancel records | Fill rate, delay, realized slippage, shortfall | Specific to size, urgency and route |
| Context | Contract, trade date, event, holiday and roll flags | Comparable state slices | Missing tags contaminate the map |
Make prices and contracts comparable
Normalize Before Drawing a Level
Keep the raw 6Z quote in U.S. dollars per South African rand and retain the exact dated contract. If a continuous series is needed for visualization, document every roll rule and adjustment and keep the raw contracts available. Express distance in ticks, basis points or volatility-scaled units rather than assuming an old absolute price band has unchanged meaning.
Validate
Resolve sequence gaps, duplicates, corrections and locked or crossed states.
Identify
Attach dated contract, expiry, session and official trading-day fields.
Normalize
Preserve raw price; derive tick distance and optional volatility scale.
Stratify
Separate time, event, holiday, volatility and roll regimes.
Version
Stamp data end date, sample, parameters and code revision.
Map distributions, not folklore
Overlay Market Quality by Regime
Choose bins before reading the outcome. Report median and tail conditions, observation counts and missingness. A level is descriptive only inside its measured contract, sample and regime.
Price layer
Two-sided trade
Executed volume, trade count and repeat visits by normalized price distance. Do not call it support or resistance.
Book layer
Spread and depth
Time-weighted inside spread, quantities through fixed tick bands, quote age and replenishment.
Flow layer
Queue behavior
Add, cancel, execute and depletion measures where order-level data genuinely supports them.
State layer
Event and roll context
SARB, U.S. releases, holidays, session transitions, migration and expiry proximity.
Worked map record
Store enough context to reproduce one cell
A map cell should be traceable to raw observations. Record the dated contract, UTC interval, local labels, sample start and end, eligible-day count, excluded-day count, feed and depth level, price normalization, event state and roll state. For spread, store a time-weighted distribution rather than only its mean. For depth, state the number of ticks included on each side and report both typical and lower-tail quantity. For traded activity, retain trade count and size distribution alongside volume so one large print cannot masquerade as continuous participation.
Consider a normalized price band that shows high historical volume but weak current depth. The map must not call it a “liquidity zone.” Mark the historical traded-volume evidence as present, the current quoted-capacity gate as failed and the order as wait or reject depending on the policy. If subsequent fills consistently cost more than the modeled sweep, open a calibration incident: verify timestamps, latency, hidden partial fills, cancellations and order size, then either widen the conservative cost bound or retire the cell. Never revise only the losing observations.
Archive each published map version. Later revisions should state which observations entered, which cells changed and whether the change came from new evidence, a corrected feed or a revised method.
High historical traded volume says transactions occurred. It does not say the same quantity will be displayed, remain available or fill at the same cost for the next order.
Use the map as a gate
Translate the Map into Order Decisions
Declare the order size, urgency, acceptable spread, depth band and maximum modeled impact. Compare current conditions with the matching historical state, then choose among execution branches. A map informs where patience may be warranted; it does not predict direction.
Eligible
Current state is represented
Contract, time, regime and book measures fall inside the validated sample for this order policy.
Reduce
Capacity is smaller
Spread passes but depth or tail cost supports only a preregistered smaller quantity.
Wait
Transient state dominates
An event burst, roll transition or unstable quote sequence requires a new observation.
Reject
Map cannot score the order
Required fields are absent, current conditions are out of distribution or the map is stale.
For a pretrade map versus post-trade cost split, route realized fill analysis to Why 6Z Slippage Can Hit Harder and actor-identification questions to 6Z Algorithmic Behavior.
A map has an expiration test
Reject the Map When Its State No Longer Matches
Recompute on a registered schedule and after material exchange, feed or regime changes. Compare recent spread, depth, trade-size and fill distributions with the reference sample. Do not silently extend a map through a contract migration, a data-vendor change or a structural break.
- Data end date, timezone, contract and roll policy are visible.
- Recent observations clear minimum sample and completeness gates.
- Current spread and depth remain inside registered distribution bounds.
- Event and holiday periods are separated rather than averaged away.
- Execution results remain consistent with the pretrade capacity model.
- Out-of-distribution conditions produce “unscorable,” not a forced zone.
No original result is reported. This page publishes no 6Z spread, depth, queue, volume-profile, fill or slippage finding; it defines the map and its rejection policy, not permanent price zones.
Sources, methods and editorial disclosure — reviewed August 25, 2026
- CME Rulebook index and Chapter 259 for the 6Z contract identity.
- CME DataMine for official distinctions among historical data products.
- BIS, FX trade execution landscape for market-wide distinctions among execution venues and protocols; it is context, not a 6Z finding.
- South African Reserve Bank MPC announcements for official policy-event timestamps used as candidate regime labels.
Sources were reviewed August 25, 2026. This unsponsored article separates exchange facts, measurement design and proposed execution use. No original market result is claimed.