Summary
This explainer uses an illustrative venue dataset — 4.1 million simulated market orders across forex, metals, indices and crypto CFDs over a six-month window — to show how execution quality should be read: the distribution, not just the average. Median, p95 and p99 execution times, slippage direction, and behavior during the six highest-impact news events of the period.
28 ms
Median round-trip in the example dataset
97.1%
Example orders filled at or better than quote
4.1M
Simulated orders in the illustration
Latency distribution
Averages hide tails. A venue quoting “30 ms average” can still deliver 400 ms exactly when volatility spikes — which is when execution matters most. Percentiles tell the truth instead.
Order round-trip latency by percentile
milliseconds — lower is better
The p99 figure includes the release minutes of every NFP, CPI and FOMC event in the window. Even the worst 1% of orders completed in under an eighth of a second.
Slippage direction is the honesty test
Slippage direction is the honesty test for any execution venue. Asymmetric slippage — fills that only ever slip against the client — indicates last-look abuse or quote manipulation. A venue handling slippage symmetrically produces a split like the example below:
Market-order fill outcomes, share of volume
% of 4.1M orders
If a venue won't publish its negative-slippage share, assume the number answers the question.
— A useful rule of thumb
Behavior under news
The example isolates the 60-second windows around six tier-1 releases. Spreads widen — that is real liquidity thinning, not venue behavior — but execution time and reject rates stayed inside normal bands:
- Median latency during release minutes in the example dataset: 34 ms (vs 28 ms baseline).
- Reject rate: 0.4% (vs 0.2% baseline) — rejects re-quote rather than silently fill at a worse price.
- XAUUSD spread at NFP peak: 3.2× typical, recovering to baseline within 41 seconds on average.
Methodology
- Population: every market order on live accounts, Jan 1 – Jun 30 2026. No sampling, no exclusions except cancelled-before-fill.
- Clock: single monotonic clock at the execution gateway; timestamps at receipt, risk-check completion, and fill.
- Slippage: fill price vs the quote displayed at order submission, signed from the client’s perspective.
- News windows: ±30 s around the scheduled timestamp of NFP (×2), US CPI (×2), FOMC (×2).
Educational content only. Figures, benchmarks and charts are illustrative examples, not IUX production data or a representation of trading outcomes. Nothing here is investment advice.