Custom Goals and %DV

I have been using this app for some time and really enjoy its ability to simplify tracking my nutritional intake. However, when I decided to change some of my nutrient goals to better fit my personal needs I ran into some issues. If I want to specify a goal of Vitamin A, Vitamin C, or Calcium it can only be done in terms of %DV. Preferably I would like to be able to enter in the amount in mg. On the other hand I wouldn't mind entering it in using %DV unfortunately, even after searching around the net, I find it difficult to determine exactly how many mg 100 %DV is, or if it changes depending on my personal profile on myfitnesspal.

Thank you for your time.