What is APR?
APR stands for Account Progession Rate. This mechanic is utilized in minigames such as Gold Rush, that will determine how much bonus gold you'll get during it. A percent between 0-100% will be generated by combining together a multitude of different factors. These include: overall level, prestiges, achievements, miniquests and collection logs.
Where can I view mine?
You can find your generated APR by clicking on the Information menu, then the Account Information tab..It'll will be the percentage at the top of the list.