Renting a room in my house for part of the year

I have rented out a room in my house for a couple of years. This past year, my tenant moved out partway through the year, so I have the tax situation where I rented a portion of my house (1 room) for only part of the year.

In previous years, I have checked the option that "I rent out a part of my home" and "Yes, this property was rented all year". I then get an option to allow TurboTax to calculate the expense deductions for me, where I enter the percentage of my property that I rent out (based on square footage). This has worked for previous years.

For this year, I checked the option that "I rent out a part of my home", and select "No, this property was not rented all year", and am then presented an option to enter the amount of time that the property was rented at fair market value and the amount of time it was used for personal use. I enter these numbers (the room was rented for 8 months of the year, and I did not rent it out after that, so the remaining time was fully personal use). But I am then not given the option to allow TurboTax to calculate the expense deductions (where I would enter the percentage rented out). This causes the final numbers to be significantly off.

Is there a way to get TurboTax to do these calculations correctly, to avoid having to do all of the calculations myself?