Hotel occupancy rates in Hawaii plunged to 63 percent in September. That is the lowest level since the 9/11 attacks in 2001.

A report by Hospitality Advisors LLC also says average daily room rates fell 2 percent. Hotel room revenue dropped by $37 million, a 17 percent decline over the same month in 2007.

Oahu hotels led in occupancy rates among the islands in September, filling 69 percent of their rooms. That is 10 percentage points lower than September a year ago. Kauai filled a bit less than 69 percent of its rooms, about 8 percentage points below a year ago.

About 57 percent of rooms in Maui were occupied in September, compared to 72 percent a year ago. Just 50 percent of rooms on the Big Island were filled, 10 percentage points less than a year ago.