My spread is a candlestick graphe. I use the following formula:
OpenSpread = Open / Foreign("BN.PA","Open");
HighSpread = High / Foreign("BN.PA","High");
LowSpread = Low / Foreign("BN.PA","Low");
CloseSpread = Close / Foreign("BN.PA","Close");
PlotOHLC( OpenSpread, HighSpread, LowSpread...