#Time decay & timing
4 public posts on this topic.
Record
Choosing an expiry for a long put — same-day, next-day, one week, one month, priced out
Same strike, same view. Change only the expiry and you pay 74× more. The real cost turned out not to be theta.
Theory
I drew the butterfly curve as it sharpens
In the morning it barely matters where you center it — every strike prices about the same. By the close, the value collects on one point. Here is how that curve actually changes, and how I picked the center.
Record
I bought a same-day put and a next-day put on the same view — one finished at −17%, the other at −100%
Same day, same direction, same reasoning. Only the expiry differed. One day's record.
Theory
I open the butterfly before price arrives — the same fly cost 3.5× more five hours later
By the time I am confident, it is already expensive. One day's record of how entry timing changed the required win rate by 3.5×.
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