Is there a staking reward calculator for voters?

Just found this article about the expected ROI:
https://medium.com/x-cash/dpops-faq-general-information-expected-roi-and-more-7e83e839c912

"The delegates could also set the fees to a minimum of 24% to pay for the server hosting service. If the delegates set the fees at 24%, the return will be 1.75% return/monthly, or 21% return/yearly on your stake net of the fees."