Short answer: Displayed overround is calculated from a complete set of market odds. Realised hold compares stakes and payouts over settled activity. Regulatory GGY follows the reporting authority’s definition and may not match an internal hold field. Put these measures in separate columns with their formula, population, currency, settlement status and period before comparing them.
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Displayed overround
For decimal odds, sum 1 / odds across every mutually exclusive outcome and subtract one. A three-way market at 2.10, 3.40 and 3.60 totals 1.0481, or 4.81% overround. This is a snapshot of quoted prices, not realised revenue.
Store the event, market, timestamp, source and active field. Comparing incomplete or differently defined markets produces a false margin trend.
Realised hold
A simple internal hold view might use settled stakes minus settled payouts divided by settled stakes. The exact treatment of voids, cash-out, free bets, taxes, commissions and jackpots must be documented. Short windows can be dominated by event outcomes rather than structural price changes.
Use cohorts by settlement date and product, and reconcile transaction states. Mixing placed-date stakes with settlement-date payouts shifts activity across periods.
GGY and source definitions
The UK Gambling Commission’s industry publications use defined Gross Gambling Yield measures from regulatory returns. An internal metric named GGR, NGR or revenue may include different deductions. Map the source definition field by field before reproducing an official comparison.
Regulatory return values are quality checked and can later be revised. Store release and retrieval dates for public benchmark data.
Build a reconciliation
Start with opening unsettled liabilities, add stakes and adjustments, subtract payouts, voids and closing unsettled liabilities under the chosen accounting policy. Tie the result to the source ledger and document residual differences. A dashboard percentage without a cash or ledger bridge is difficult to trust.
Report sample size and uncertainty. A market with ten settled bets should not be ranked beside one with a million solely by realised hold percentage.
Three margin concepts
| Measure | Inputs | Best use |
|---|---|---|
| Overround | Complete quoted odds | Price snapshot |
| Realised hold | Settled stakes and payouts | Operational outcome with variance |
| GGY | Authority/source definition | Regulatory and industry reporting |
| NGR | Company-defined deductions | Internal finance; definition required |
Continue inside this guide
- iGaming analytics dictionary
- How to read iGaming data
- Compliance reporting
- Responsible gambling metrics
Sources and scope
Sources were checked on 12 August 2026. They support the definitions and consumer checks below; they do not endorse this site or any gambling decision.
- UK Gambling Commission: industry statistics definitions
- UK Gambling Commission: industry statistics methodology
- UK Gambling Commission: industry statistics 2024 to 2025
FAQ
Is overround the same as realised hold?
No. Overround comes from quoted prices; realised hold comes from settled transaction outcomes over a period.
Can GGY equal an internal GGR field?
Only if the definitions and deductions match. Document a field-level mapping instead of assuming the labels are synonyms.
Why can short-term hold be negative?
Event outcomes and small samples can produce large variance even when prices contain positive overround.
Related checks on this site
These routes connect this answer with closer checks, methodology and fresh local coverage.
