Minimum transaction fields
| Group | Fields to preserve |
|---|---|
| Identity | Stable bet ID, operator or exchange, account currency, placed timestamp |
| Contract | Event, competition, market, selection, qualifying period, rule URL or version |
| Acceptance | Requested price, accepted price, stake, commission basis, promotion identifier |
| Forecast | Probability, model or method version, data cutoff, recorded timestamp |
| Settlement | Status, gross return, commission, tax if applicable, net result, settled timestamp |
| Audit | Receipt reference, correction reason, previous value, corrected value, correction time |
Do not reconstruct an alleged pre-match forecast after seeing the result. A forecast field is valid only when its value and data cutoff were stored before the event. For exchange analysis, the Betfair historical-data specification illustrates why timestamp, market status, available prices, traded volume, commission, and market timing are separate fields.
Worked reconciliation
Assume four illustrative settled rows:
| Bet | Stake | Gross return | Net result |
|---|---|---|---|
| A | GBP 10 | GBP 18 | GBP 8 |
| B | GBP 5 | GBP 0 | -GBP 5 |
| C | GBP 15 | GBP 24 | GBP 9 |
| D, void | GBP 10 | GBP 10 | GBP 0 |
| Total | GBP 40 | GBP 52 | GBP 12 |
Net result for a simple fixed-odds row = gross return - stake. Here, total net result = GBP 52 - GBP 40 = GBP 12. Return on stakes = GBP 12 / GBP 40 = 0.30, or 30% for this illustrative set. Ratio analysis requires the numerator and denominator to be defined consistently; ACCA's ratio guidance explains why like-for-like definitions and context matter.
Four rows are a reconciliation example, not evidence of a stable return. Do not annualize it or use it to set a future stake.
Track forecast quality separately from money
Profit depends on stakes, prices, settlement, and outcome. Forecast quality asks a different question: whether stated probabilities correspond to outcomes. For a binary event, the Brier component is (forecast probability - outcome)^2. A 0.70 forecast followed by a win coded 1 has squared error (0.70 - 1)^2 = 0.09. The original Brier paper establishes probability-forecast verification; compare only consistently defined events and horizons.
Preserve corrections
Never silently replace a price, status, or return. Add the corrected value, reason, source, and timestamp while retaining the previous value. Spreadsheet tools can help locate broken references, but formulas still require review. Microsoft's formula-error guidance covers error checking and evaluating a calculation step by step.
Monthly verification
- Match every row to an accepted receipt.
- Reconcile stakes and returns to the account statement.
- Review voids, pushes, commission, promotions, and corrections.
- Test formulas on known rows and totals.
- Separate results by currency and settlement basis.
- Report missing data instead of filling it from memory.
- Freeze the reviewed period and record the review date.
Next step
Use Bankroll Spreadsheet Template for the next part of this topic.
Continue learning
- Next guide: Weekend Football Betting
- Related guide: Football Betting for Women
Assumptions and limitations
The ledger is a general analytical structure, not accounting or tax advice. Product settlement, commission, deductions, currency conversion, and reporting obligations vary. Closing-price comparisons require a specified source and timestamp. Historical performance and forecast scores do not guarantee future results.
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