THIS SIGN DOES NOT EXIST
With three lanes dividing here (the rightmost one being from the U.S. 52 on ramp), a Phoenix-style sign seemed the only option. Does not the single line down the middle clearly indicate that the middle lane is the optional lane while the left and right lanes are mandatory left and right exits, respectively? Oh, and yes, in real life there are stoplights here. Yuck.
US 20 - US 61/151 Interchange at Dubuque, IA