ThetifyDaily scenario: SPY 2018-12-24
SPY, 2018-12-24: spot $209.64. You are short the $233 put opened at $2.12, now $23.66, 30 DTE. IV 24.5% vs HV 21.3%. Holiday-shortened session; S&P 500 fell 2.7% and closed 19.8% below its September high.
- AHold the position
- BRoll out: same strike, later expiry
- CClose the position
- DTake profit: buy it back
What would you do?
The answer and the worked numbers for every choice are in the Thetify app.
Where the position stood
| Underlying | SPY |
|---|---|
| Date | 2018-12-24 |
| Stock price | $209.64 |
| Position | Short the $233 put |
| Stock vs strike | 10.0% below the strike (in the money) |
| Opened at → now | $2.12 → $23.66 |
| Implied volatility (IV) | 24.5% |
| Historical volatility (HV) | 21.3% |
| Days to expiration | 30 |
Under this scenario’s assumptions. Every number in this table is already in the scenario text above; nothing comes from what happened afterwards.
Run these numbers yourself
Open the calculator with this scenario’s price, strike, days, IV and HV already typed in, and read the premium, delta and probabilities for yourself. The calculator leaves out dividends, so its readings can differ slightly from the scenario’s own.
Terms in this scenario
- DTE (days to expiration): The number of calendar days left until the contract expires.
- Implied volatility (IV): The volatility figure that makes the model price equal the price the option actually trades at.
- Historical volatility (HV): How much the stock actually moved over a past window, stated in annualised terms.
Same kind of decision
Three more scenarios of the same kind: managing a short put.
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