Percent has a different meaning than percent point.

The UI's tooltips often uses the symbol % to incorrectly indicate pp. This is especially confusing because typically games will include a mix of pp and % yet call them both % as if they are the same thing.

Granted pp is not a well known symbol so I would suggest using "%p" with a hiergamenon entry clarifying. (even though the official recognize symbol for percentage point is pp and %p is not)

For example, any building the reduces unrest by X% actually reduces unrest by Xpp. 10% reduction of 20% unrest = 18% unrest. 10pp reduction of 20% unrest = 10% unrest.

While buildings that give out bonuses to gildar, research, food, and production give a % of base value bonus (or pp bonus to a multiplier). So for example on gildar. 10G +20% +20% = 14.4G. But the game actually gives you 10G + 10G*20% +10G*20% = 14G