How to Determine the Logic Behind the "Dispon.TOT1 BRL" Field in CJE0?

Hello Community, I have a report generated through transaction CJE0 that contains a field called “Dispon.TOT1 BRL” (Available Total 1 BRL). I need to replicate the logic used to calculate and retrieve this field in a custom Z report . My challenge is that CJE0 generates a dynamic report (for example, GPB48XT8AO26F83MVQSWVIN7UU0 ), and I have not been able to identify where the system reads the underlying tables or performs the calculations required to display this particular field.