Home office for wife's freelance business... property tax deductions?

When I went to enter our usual property tax deductions of $14887, and then I decided to thoroughly investigate the home office deduction side of things as my wife's income is growing rather substantially. It prompted me to enter the property tax on that section, and now when I go to review it shows (14887+14887-828 = 28946) as property taxes, which is obviously about double the previous year. SO, I'm either screwing things up royally, OR I need to go back to last year's return and re-file. 

Anyway, I'm looking for a little advice. Yes, she 100% works from home and I mark ~6% of the home as her workspace.