Calendar-day theta
Definition · Level 5 · Greeks & volatility
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Theta counted for every calendar day, so a weekend counts three days; dealers often price part of the weekend’s decay in before Friday’s close.
Example
Theta +$360 a day: Friday close to Monday close accrues about $1,080.
Rules and market figures change: check the current ones before relying on this.
Where Tradecraft teaches it
Level 5 · Greeks & volatility, in the lesson “Theta: the rent for owning gamma”: The daily cost of time, why it speeds up, and the daily move you need to break even.
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