Monday, 3/8/2021
sell -1 March 10, 2021 3665 put at $2.29 (5.31% prob ITM)
buy +1 March 10, 2021 3620 put at $1.09 (2.63% prob ITM)
net credit: $1.20
margin: $4371
Tuesday, 3/9/2021 (SPX up 80)
buy back short put (3665 strike) at $0.20
Tuesday, 3/9/2021 (8 minutes later)
sell -1 March 10, 2021 3790 put at $1.20 (4.78% prob ITM)
new margin: $16,887
Wednesday, 3/10/2021 (Expiration)
SPX closed at 3898.81
Let entire put spread expire "worthless"
NET PROFIT: $215.13 (in 2 days)
Return on capital: 232% (annualized)
Learn to trade options!