Substitution coefficient Q to calculate loss factor by circulating currents

Definition for flat arrangement is according to IEC 60287-1-1 clause 2.3.3
Definition for rectangular arrangement is according to publication 'General Calculations Excerpt from Prysmian Wire and Cable Engineering Guide' (2015)

Symbol
$Q_{X}$
Formulas
$X_{e}-\frac{X_{m}}{3}$flat
$X_{e}-\frac{X_{m}}{6}$rectangular