Form 8615 line 9

I'm asked suddenly to populate line 9 in the form 8615 worksheet (just a popup window) about what portion of line 8 is directly connected to the production of the unearned income. How do I determine this? Line 8 is her itemized deduction. If all her income is unearned, would the amount in line 9 be the same as line 8? I would think it's 100%. Any ideas?