If you want the numbers to count down from high to low, I’m not sure you can do that without scripting. The text variable in a numbered list is set to increment without having an option to decrement instead. So… short of scripting it… I think you’d have to do a workaround.
If this is just one list, I’d be inclined to do a (somewhat messy) workaround and be done with it. But if you’re going to have numerous instances of a reverse-numbered list, then I’d try to do it via scripting.
My very messy workaround would be: select the entire list and convert numbering to text. Assuming your style used Tab characters, this now gives you a fake-numbered list.
1.<TAB>Apple
2.<TAB>Banana
3.<TAB>Cherry
Select the entire list and convert it to a table, using Tab as your column separator. Now if you have the Smart Styles plug in for ID, you can sort the column in ID. Otherwise, select just the column with the numbers in it, copy/paste it into Excel, reverse sort it there, copy/paste it back into ID. Finally, select the table and convert it back to text.
Again, this would be my workaround only if this was the only list I was going to need it for. Someone may have something better.
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