Diamond sells to retailers at different percentages, based on their order volume. The scales are different for Marvel, DC, Image, Dark Horse, and for Everyone Else, and some of them top out at 58.5% for the largest of the large accounts (I think — I would need to look again at an order book to refresh my memory). So the publisher is getting something like three-eighths of each dollar — to divide up between creative, production, printing, profit, etc. I do not have a breakdown handy on those, as it differs for each publisher. And as Bill says, not every publisher has the same terms with Diamond, so the size of the pie wedge differs.
I recall editing an article that did those breakdowns about a decade or so ago — I will look it up when I have time.