Skilled nursing occupancy rates hit their lowest level on record in the fourth quarter of 2016, according to the National Investment Center for Seniors Housing & Care.

The group’s Skilled Nursing Data Report for the fourth quarter showed the national occupancy rate fell from 82.6% to 81.8%, the lowest level since NIC began collecting data in 2011.

The occupancy drop came amid an “early and significant flu season,” which likely helped boost skilled mix but didn’t bump occupancy like it has in the past, according to Bill Kauffman, senior principal for NIC.