but trying to calculate an opening bid using pre-market data doing the same with spy <img src=http://img257.imageshack.us/img257/1146/14856447kq9.gif> <pre> Symbol OEYEQ Type OEX MAY 2007 685 Call Bid/Ask 4.80/5.00 Delta 0.4859 Gamma 0.0307 Expires (days) 7 Implied Vol. 13.7065 1 Day Decay -0.4167 Time Premium 4.90 Intrinsic Val 0.00 Stk Price * 683.73 Off-Target 2.72 3.00 6.45 > 2.75 6.31 2.50 6.18 2.25 6.04 2.00 5.90 1.75 5.77 1.50 5.64 1.25 5.52 1.00 5.39 0.75 5.26 0.50 5.14 0.25 5.02 0.00 4.90 -0.25 4.78 -0.50 4.66 -0.75 4.54 -1.00 4.41 -1.25 4.30 -1.50 4.19 -1.75 4.07 -2.00 3.96 -2.25 3.85 -2.50 3.75 -2.75 3.64 -3.00 3.53 Loaded 9:20:02 AM ET </pre>