The voting power should remain between about 75-85 for the majority of the time. As of right now it is 77:

Upvu was 79 and justyy was 78 last time I checked, so we are not too far out of where they are. There are going to be times during the day when more upvotes are made and voting power is lower, like perhaps when you have been checking. The recent drop was due to a large delegation being removed that pushed the voting power lower than it had been.

That being said we are monitoring it and will keep an eye on it. If voting power gets too low, we may have to adjust the multiplier for upvotes from 20x to 18x, but we have no plans of doing that just yet and we would make sure to let everyone know well in advance before we ever made that move.