You can plot any mathematical relationship, then make the two charts Hidden and just view the spread - or use a different y axis for the spread...
today at 930 ny time is the rollover, watch the volume in es m3 to confirm
http://forum.esignalcentral.com/showthread.php?s=&threadid=1021 has your idea posted for discussion by the eSignal folks
eSignal has a backtesting facility and a lot of users who help others get started in their forum area. www.esignal.com
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