I'm curious if anyone has ever tallied the expenditures of all of the world's space programs, and then tried to divide it by which planet was targeted. It's possible this has already been done.
If not, would it be possible to make an estimate, or even a guestimate based on available data and compilations?
If a missions budget is not available, an estimate based on any similar missions would be fine, this isn't rocket science. If a mission visited several bodies, then its budget could just be divided evenly or perhaps unevenly as seen fit.
For the purposes of this question, the Sun, the Moon, and Pluto all get to be "planets" because replacing "planet" with "body" makes the title of the question sound creepy. We can skip the missions to study Earth as well.