Use Gainers / Losers and Market Share

Ranking and distribution are different questions

Gainers / Losers ranks symbols or contracts using the selected measure, which can include directional premium, volume or price change. Market Share groups selected premium, volume or trades by exchange or venue group. A leading ticker and a leading venue are not competing answers to the same question. Read the title, selected mode and measurement before interpreting a percentage or rank.

Choose one basis for comparison

Both tools become easier to reconcile when you start with a bounded symbol set and one session.

1. Open Gainers / Losers or Market Share from the Statistics tools.
2. Choose symbol versus contract ranking where available.
3. Select premium, volume, trades or the offered price-change measure.
4. Set session/date and supported filters.
5. Inspect a row or venue's amount alongside its share or rank.
6. Match the same selection in Contract Statistics to compare totals.

Shares need a selected denominator

A venue's share is a proportion of the selected admitted activity. It is not automatically the share of all US securities trading. Premium-weighted share can differ from contract-weighted share. A price gainer is also different from an activity leader: one compares prices with a reference, while the other ranks an execution measure. Read the reference close and available freshness before treating a price-change percentage as current market leadership.

Worked example: one venue leads premium but not volume

Suppose Venue A has a smaller contract count but more expensive selected executions than Venue B. It can lead premium share while trailing volume share. Switching the measurement changes the denominator and ranking legitimately. Similarly, a contract with the largest percentage price increase can have little executed volume. Compare the amount and sample coverage instead of using a prominent rank alone as evidence of market-wide importance.

Troubleshoot moving ranks and mismatched totals

Live ranks can change while you inspect them, and different symbol scopes alter shares. Confirm whether one widget is market-wide while another is linked to a family. Read partial capture and reference-date notices. If a percentage looks impossible, capture the selected measurement and its amount/denominator fields together. A screenshot of a rank number without its mode, filters and timestamp is not enough to reproduce the calculation.

Align filters, measurements and coverage

Premium, contract volume and trade count measure different things. Ten contracts at a high option price can contribute more premium than many contracts at a low price. Gross premium, signed net premium, call-minus-put drift and an individual time bucket are also different aggregates. Before reconciling tools, match the symbol family, exact roots where relevant, trading date, session, expirations, call/put choice, size and premium thresholds, aggressor filters and any trade-type selection.

A live stream can begin after the session started. Its current rows may be fresh while an earlier prefix is missing. Historical repair can add eligible prints and recompute older totals without representing new live trades. Empty filtered results mean no admitted matching rows, not necessarily no market activity. Read the reported source times, observed bounds and partial-coverage state. For an apparent mismatch, reproduce it with broad filters first, then add one filter at a time and compare the same measurement over the same time interval.

Use scope and reference values to explain rank changes

A price-change rank needs a reference price and a usable current observation. A premium rank needs selected executed premium. A venue share needs a selected total across included venues. Those denominators should be written beside screenshots. If you restrict the symbol universe, a venue's percentage can rise even while its absolute admitted amount falls. If you change from contracts to tickers, several contract contributions can combine into a different leader. Neither effect by itself indicates a calculation error.

A careful comparison holds the session and symbol scope constant, changes only the measure, then explains which weighting drove the result. Check whether market-wide widgets are unlinked while nearby widgets follow a colored selection group. A page header alone does not guarantee their universe matches. For a disputed rank, identify the exact ticker/contract and field rather than its current row number. For a disputed share, include amount, denominator, venue grouping and source cutoff. This preserves a reproducible numerical question even while live rankings continue changing.