Some enlightenment on this esoteric subject matter would be appreciated. Ok, so here's my dilemma based on these facts: 1) I want to indulge myself by buying the SPY call tomorrow. 2) My holding period is exactly 3 days. 3) The premium for the weekly options is cheaper than the quarterly options. 4) 3 days being less than a week (and weekly premium being cheaper), it's more intuitive to buy the weekly than the quarterly. The unknown is the "time decay". For some reason, I feel I would lose more on the weekly due to a bigger time decay. Considering that I buy the call tomorrow, the weekly has roughly 6 days until expiration and the quarterly about 15 days. Can anyone shed some light on what the rate of difference is between the two options for, say, the next 3 days?