Start with wins divided by wins plus losses, but label what counts. Keep an official-decision rate, which may include fusen outcomes, separate from a contested-bout rate based only on matches that took place. Do not convert absent days into losses. Publish the rank range, dates, wrestler count, bout count and formula beside the percentage.
The official scorecard distinguishes ordinary results, defaults and days of rest or no bout. Subtracting absences from fifteen is not a reliable shortcut, especially for mid-tournament entry, withdrawal or lower-division schedules. Build a bout-level table from the official marks.
Three measures answer three questions
An official win rate follows recorded wins and losses. A contested-bout rate excludes defaults so it describes action on the dohyo. A participation measure compares appearances with possible opportunities under a declared rule. Name each measure instead of allowing the word “strength” to stand in for all three.
The average of wrestler-level rates also differs from a pooled rate. An unweighted average gives a wrestler with two bouts the same influence as one with fifteen. Pooling all wins and bouts gives more weight to wrestlers who appeared more often. Either may be useful, but the weighting must be visible.
Align the comparison
Do not mix makuuchi with lower divisions, career records with time at one rank, or debut tournaments with mature careers. Cross-era analysis must check tournament and bout structures before treating rows as equivalent. For a small sample, show the win-loss count and preferably an interval rather than presenting one decimal place as certainty. Freeze the population by division, rank, interval and extraction cutoff; count unavailable or unclassified records as missing. Right-censor tournament follow-up at the last officially completed day, but calculate win rate only from observed bouts: future bouts are not missing losses and never enter the denominator early.
A result of 59.7 percent versus 60.0 percent is not meaningful by itself. Inspect denominators, missing records and variation first. When an official record is corrected, retain which bout changed and rerun the calculation from source rows; do not simply overwrite the final cell.
The bout outside the decimal
After studying a rate, watch for one first choice before you look at the winner. Two wrestlers can arrive at an identical percentage through very different fifteen-day stories—steady forward pressure, late escapes, defaults or interrupted participation. Win rate is a useful doorway, but the detail that makes you follow a wrestler often lives outside the decimal.
Counterevidence and the Update Trigger
The result is limited to the stated period, population and missing-data treatment. An official correction, a newly completed tournament, a changed exclusion rule or a failed recalculation is an update trigger. Preserve the previous value, reason for change and recalculation date; do not strengthen a conclusion using only convenient new records. Recalculate official-decision, contested-bout and opportunity denominators from identical bout rows as falsification checks. If the order or gap reverses, publish denominator-sensitive as the alternative conclusion.
Sources
- Japan Sumo Association, tournament scorecard, daily bouts/results, and wrestler search (checked 3 September 2026; recalculate after tournament completion or official correction).
Source links used for verification
Each link was used for the corresponding claim in this article; inclusion is not a blanket endorsement of the whole page.
Article verified:
- Japan Sumo Association tournament scorecardPrimary source (as checked for this article)
- Japan Sumo Association daily bouts and resultsPrimary source (as checked for this article)
- Japan Sumo Association wrestler searchPrimary source (as checked for this article)