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Bell Curves

Bell Curves shows what option spreads were typically worth in the past when the ATM straddle stood at a given level. Pick an instrument, slide to a straddle level, and the familiar butterfly, ratio, pulse and combo sheets fill with historical values instead of live prices.

ShowsTypical past value of each spread cell, grouped by ATM straddle level
LayoutFilters and stats on the left; Combo Butterflies, Ratio, Custom Butterfly, Butterfly (1:2:1) and Pulse (1:3:3:1) sheets on the right; straddle slider at the bottom
DataBuilt from the 1-minute archive of the nearest expiry; median across days of each day's average
InstrumentsIndex options and MCX commodities that have a built history appear in the Instrument list
UpdatesRebuilt nightly after the day's data is archived
History60D, 90D or All trading days
Open itquintalmind.com/analysis/bell-curves

What you see​

The straddle here is the ATM (at-the-money) straddle: the price of the ATM call plus the ATM put. Past minutes are grouped into straddle bands (buckets). For each band:

  1. For every past day, each strike's call and put price is averaged over the minutes when the straddle sat in that band. Strikes are measured relative to ATM, which is re-set every minute from spot.
  2. Across all the days in the window, the median of those daily averages is taken for each strike.
  3. The spread cells are then built from those median leg prices, using the same legs as the live sheets.

So a cell answers one question: "when the straddle was around this level, what was this spread usually worth?" It is a summary of the past, not a forecast.

The left panel shows:

  • Instrument, Window (60D, 90D or All) and DTE (days to expiry; available on the All window).
  • Window dates, Total Dates, the current Straddle band and Minutes counted.
  • Dates in Bucket (Click): how many days had the straddle in this band. When only a few days back a band, a Thin sample note appears.

The bottom bar shows the symbol, window, number of dates and DTE, with the STRADDLE slider to step through the bands.

How to use it​

  1. Sign in with your broker and open Bell Curves, or go to Analysis.
  2. Pick an Instrument and a Window.
  3. On the All window, choose a DTE or leave All DTEs.
  4. Drag the STRADDLE slider to the level you want to study.
  5. Use the − and + buttons on each sheet to change the range of wing widths.
  6. Click Dates in Bucket (Click) to list the days behind the numbers and open any of them in Historical Sheets.

FAQ​

What did a NIFTY butterfly typically cost when the straddle was at a given level?​

Quintal Mind's Bell Curves page answers this. Move the straddle slider to a level and the sheets show the typical past value of each butterfly, ratio, pulse and combo cell at that level.

How is the typical value calculated?​

For each past day, leg prices are averaged over the minutes when the ATM straddle sat in that band. The page then takes the median of those daily values across all days in the window and builds the spreads from them.

Can I filter by days to expiry?​

Yes. On the All window, the DTE list splits the history by days to expiry. The 60D and 90D windows cover all DTEs together.

Can I see which days are behind a value?​

Yes. Click Dates in Bucket to list them. Each date opens that day in Historical Sheets.

Quintal Mind shows market data and analytics for information only. Nothing here is investment advice, and Quintal Mind does not place orders.

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