There are two basic percentage questions you may be asked. Here's the clarification.
Percentage of property rented - the total square footage of floor space that is exclusive to the renter(s)
Percentage of time rented - Of the total square footage that is rented, what percentage of the time from the date you placed it "in service", was it used for business? This will be one hundred percent. Likewise, the percentage of time it was used for personal use *ONLY* during the time it was classified as rental space, will be ZERO percent.
