The regulation of long-term changes in the load resistance of a power supply is called:

Power supply regulation can be evaluated based on how the supply responds to changes over different time frames. 'Static regulation' refers to the supply's ability to maintain a constant output voltage over long periods despite slow, steady (or 'static') changes in the load resistance. This is often calculated simply by comparing the steady-state no-load voltage to the steady-state full-load voltage. Because the changes are long-term and steady, the term 'static' is appropriate. By contrast, 'dynamic regulation' deals with fast, transient changes. Distractors like 'active' or 'analog' regulation do not describe time-based load response characteristics.