So many people are getting confused by this. Your display isn't using any more power than it was before. Before it only displayed percentages for the amount of battery that was alright used up. So a bunch of things were around 5% each, and these added up to the total percentage of the battery charge that had been used. 60% or some large number was the amount of battery remaining (but wasn't displayed under battery).
Now they account for the entire battery, so the numbers add up to 100%. As you use more things, these percentages will fluctuate. They don't separate the used battery charge from the remaining battery charge to calculate their percentages.
Before: "Of the 30% of your charge you've used, 4% was used by the display". Now: "Your display is using 80% of the power that is being consumed right now."