Zero-line Volatility Quality Index (VQI) [Loxx]

Originally volatility quality was invented by Thomas Stridsman, and he uses it in combination of two averages.

This version:
This doesn't use averages for trend estimation, but instead uses the slope of the Volatility quality. In order to lessen the number of signals (which can be enormous if the VQ is not filtered), some versions similar to this are using pips filters. This version is using % ATR (Average True Range) instead. The reason for that is that :

• Using fixed pips value as a filter will work on one symbol and will not work on another
  
• Changing time frames will render the filter worthless since the ranges of higher time frames are much greater than those at lower time frames, and, when you set your filter on one time frame and then try it on another, it is almost certain that it will have to be adjusted again
  

Additionally, this version is made to oscillate around zero line (which makes the potential levels, which are even in the original Stridsman's version doubtful, unnecessary)

Usage:
You can use the color change as signals when using this indicator