Beginning tomorrow, The Art Institute of Chicago will begin requiring patrons to pay an admission fee.

For years, The Art Institute allowed visitors to decide how much to pay to view its collection, although it suggested patrons pay $12.

The museum’s director of public affairs, Erin Hogan, says nine out of 10 people did pay that price. But now, $12 will be mandatory for those 12 and older. Hogan says another change in store should boost accessibility.

“We were concerned that not enough Chicagoans, not enough working Chicagoans, were available to take advantage of our free hours. What we decided to do was move our free hours from Tuesday, to Thursday and Friday evenings,” she said.

The changes come on the heels of a study showing a lack of visitation to Chicago museums by low income residents, but Hogan says the Art Institute was talking about the changes well before the study was released in early spring.