The indicator is a normalized oscillator. 

0.66 The red line shows StdDev 2, the light green line -0.66 shows StdDev-2.

The indicator needs about 2000 bars or even more due to the normalization of calculations.

• VSO Period: The VSO period. Default 24;
• Normalize Period: the period of normalization. Default is 1000;
• VS Period: Variable Stop period. Default 120;
• VS Multiplier: Variable Stop multiplier. Default is 3.0;
• VS Spread: calculated automatically when below zero, calculated with a value at zero or higher. Default value is -1; 
• Draw Level Lines: display levels, true or false;
• – Extreme Over Bought Line: red by default;
• – Over Bough Line: Default FireBrick color;
• – Center Line: Center line, default DimGray color;
• – Over Sold Line: Default color is DarkGreen;
• – Extreme Over Sold Line: default light green color;
• Indicator ID: indicator ID, default 0;
• Display Indicator Bars: the number of displayed bars, 2000~5000 is recommended, at values above 5000 the indicator is drawn slowly. Default is 3000;
• Error Message: displays an error message, true/false.