Rental income and expenses

At what point does Turbotax allocate the percentage of expenses for property rentals? I am entering all my expenses (and my property rental is 20% of my property, meaning only 20% of the expenses should be taken). Turbo tax does not allocate and leaves me with the entire expense, which inflates my  deductions to 100% instead of the 20% needed. Has anyone else noticed this problem? At this point I will enter the allocated amounts myself.