Incorrect costs for Researchers

Help states that Researchers cost 18 Gold per hour, however they actually cost 21 Gold per hour.

Quote from Draxo

Government form?

Technocracy, so +1 gold per researcher. As far as I can see there are no server settings that effect this.
Server settings are: Pillage Gold and Battle Sans Morale.

Also, I have not completed the research that gives -3 gold per researcher.