Disbands a percentage of the army (just the army), returning equipment and manpower to the stockpile. Useful to eg. force an AI to reduce the size of their army after a war.
SOL must be replaced with a tag from your mod that never exists (a utility tag).
Please note that the size is rounded up to divisions. For example, if you have 4 divisions and want to disband 1% of the army, then one division will be disbanded. This is unavoidable. Which divisions are disbanded is also completely random.
Usage example:
# disband 10% of the army of the current tag
set_variable = { disband_fraction = 0.1 }