PORTLAND, Maine (AP) About 200 people have registered short-term rental units in Portland, Maine, but officials are expecting more waves of sign-ups as a registration deadline approaches.

People renting homes and apartments through services like Airbnb have until Jan. 1 to register with the city or face a fine of $100 a day.

The Portland Press Herald reports that the number of registrations remains far below the number of rentals advertised online. The newspaper says Airbnb’s website alone shows 950 listings.

The city’s director of permitting says he hopes more people will sign up by year-end, instead of waiting for the city to track them down for noncompliance.

The city passed rules earlier this year requiring annual fees for short-term rentals and capping the number of units not occupied by their owners.