Profitable Trade: Coca Cola (KO) Puts

Yesterday the following puts expired worthless in a taxable account:

01/11/2011    STO 4 KO Feb 18 2012 65 Puts @ .51                +190.95

Coca  Cola was trading at ~69 at options expiry. The margin maintenance on this trade was $4400. We earned $190.95 in 39 days. This equates to a return on margin of 4.34% or 40.61% annual.