This indicator is a ported MQL5 indicator from http://www.mql5.com/en/code/517
Download:
For this indicator must be installed Averages indicator from viewtopic.php?f=17&t=2430
Positive Volume Index is available here.
viewtopic.php?f=17&t=7886&p=111564
Volume Index is combination of two.
viewtopic.php?f=17&t=65176