What does the turbocharged A/R value mean?

What does the turbocharged A/R value mean?

The A/R value refers to the geometric characteristics of the compressor housing and turbine housing.
The "R" (Radius) represents the distance from the center of the turbine bearing to the center point of the cross-section of the compressor outlet (turbine inlet) after completing a full 360-degree rotation around the circumference of the turbine radius line.