Halve Ticks

I want to create an area effect cloud that copies the effects an entity has. My current work already works well.. data modify entity @n[type=area_effect_cloud, distance=..0.1, tag=barhor.endow_cloud] potion_contents.custom_effects set from entity @s active_effects ..however, now I want to halve the duration of the potion effects in the area effect cloud. How could I do this? I already know how to halve a single potion effect, the issue is that an entity can have however many effects possible on them, so how could I account for any number of effects???