We are a non-profit association and we would like to have a membership fee adjustment for our new members during registration who are having residence in a country depend on the annual gross national income. (Country A-B-C) and we would like to reduce the membership fee 25% for Country B, and 50% for Country C. Country A has no discount. how can we make it automatic? I saw that there is a multiplier, but there is no such an option to reduce the fee either using minus or divide function. Can someone know how can we handle this? Thank you.