OBV Question for Simon

[Zanzibar]

What program does SBF use to generate its Price Charts? It seems that the OBV is calculated for the period chosen. On Sharemagig the OBV will stay below the Zero Line, regardless of period, once it moves into that territory. Example is KAP. on the SBK Price chart its OBV for 1 year period is in the positive, but on a 3 year period it is below the Zero Line.