Histograms of unloaded isotopic relative differences for a variety of loading isotopic compositions, when adding thermal-hydraulics coupling, with regard to isothermal core models, plutonium isotopes, for UOX and MOX fuels, for PARITE and TIER fuel loading managements. The fuel loading management correspond to 4-rounds (PARITE) and 3-rounds (TIER) MOX and UOX irradiations, as described in [14]. Histograms are stacked with a width of 0.1% relative difference value. The references are the multi-physic simulations.