This bug is a part of list found by Russian Wikipedia community in Chart extension after it was enabled on ruwiki for population graphs.

Feature summary (what you would like to be able to do and where):
Add support as a parameter to a #chart call that will allow to invert X or Y axis.

Use case(s) (list the steps that you performed to discover that problem, and describe the actual underlying problem which you want to solve. Do not describe only a solution):
This is useful for displaying charts of ratings or positions where 1 is the top and the rating decreases with the position, like FIFA ratings or any competitions. The workaround is to multiply the data values by -1, but these minuses are obviously displayed in front of numbers on Y axis.