It is irrelevant, whether the groups are filled or not, waste means how much less soap I will have compared to the recipe, and it gives the number which I can divide into portions (groups).
So when I say that for some reason I had to throw away half of my batch, I set it to 50% -> if my recipe would give 1000 g soap, now there is just 500 g soap from which I can create portions, groups, so it substracts 1000*0.5 from the recipe's gram.
But instead of this, when I set it to for example 50, it does exactly this:
1. It takes the grams from the recipe - in the attached example it's
1427.92 grams.
2. Subtract the 1% of it
1427.92 * 0.99 =1413.6408
3. Then it takes the set number (50), and instead of decreasing the value by 50% (
1427.92*0.50), it adds 50/100
1413.6408 + 50/100 = 1414.1408
Instead of this:
1427.92 * 50/100
Happens this:
(1427.92 * 0.99) + 50/100
You can see these exact values in the attached pictures.
So regardless of the set value, an initial 1% reduction is happening, then there is an addition instead of multiplication. (By the way, I wasn't able to set 0% neither to waste nor expected shrinkage)
I hope this helps clarify the problem.