Percentage difference is always relative to one of the items.
I.e. the factors are either 36/96 or 96/36.
If the reference is the 96" width, then difference is 96-36=60, and the percentage difference is 60/96=5/8=0.625 or 62.5%
If the reference is 36" (yes, usually the first mentioned item), the difference is still 60, but the percentage difference is 60/36=5/3=166.7%
