Open is total contracts (roughly like total shares)You got me.
(That is why I write "eyeballing" the charts.) I don't know enough to have reasons for the Price. But my eyeball Max-pain Number is a lot closer than the printed Max-pain price quite often.
Now educate me... I figured the "Volume" was how much was wrapped up in deals. Whereas since the "open interest" is "open" it is what is being offered...like an "open" contract isn't as secured.
Volume is the number of transactions (like shares traded)
Writing a contract contracts adds 1 to each.
Buying to close adds 1 to volume and subtracts 1 from open interest.
Buying and selling a contract adds 2 to volume and 0 to open interest.
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