Erratic values from the WPR (Williams) indicator

 

I have been working with the iWPR indicator quite a bit, and have discovered that it sometimes returns nonsense values not at all related to the position of the indicator line on the visual charts. This of course upsets the program logic. My analysis so far is leading me to believe that it might be related to the "calculate on first trade of the bar" (typically implemented as {volume[0]<=1} ) qualifier.


Has anyone else experienced this issue? Is there a workaround? And is there a better way perhaps to force a trade decision to occur only once per bar?
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