A stacked output is a sum of source voltage and flying-capacitor voltage. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Stacked output has a source part and a flying-capacitor part
A one-factor scan can hide the topology; this cross scan keeps both addends visible.
Vout=Vs+Vfly
Either addend moves the stacked output
The first three rows change the source rail; the next three rows change the flying-capacitor voltage.