"The room gap is happening and it's getting worse. We've got to blow up our current practices," said Christine Shimasaki, CMP, executive vice president of sales and marketing, San Diego Convention and Visitors Bureau. She spoke at a packed session about measuring hotel room pick-up on citywide conventions at the recent International Association of Convention and Visitor Bureaus annual meeting in Vancouver.

Shimasaki and her colleague, Sue Davis, director of special projects, SPIE/The International Society for Optical Engineering, proposed a registration-based pick-up formula quite unlike anything currently in use. Acknowledging that hotel pick-up reports are off by as much as 30 percent because of attendees who go "around" and "outside" of the block, often due to booking via the Internet, Shimasaki and Davis suggested a new formula, called the Attendee Origin Audit, that would calculate peak room night pick-up based on total registration, less those attendees who are local, divided by a double occupancy rate (based on the meeting's history).

Davis, one of many planners the San Diego CVB has surveyed about the problem, is as concerned about being able to book a convention center far enough out as she is with potential attrition penalties due to the ever-widening room gap. That's because most CVBs have booking guidelines for the convention center based on hotel pick up. "We are not going to book 20 years out a convention with little room pick-up. We're going to wait and see if we can't get a better piece of business," said Shimasaki. According to San Diego's current guidelines, for example, Davis would not be able to book a convention in at the center more than three years out because her most recent convention pick-up report showed only 1,382 rooms, out of total attendee registration of 5,226. But, using the new formula, her convention actually used 2,885 room nights. The difference? Being able to book her dates seven to ten years out versus under three, since San Diego requires a minimum of 1,500 room nights on peak night to book more than three years out.

When she has gone back to the contracted hotels and asked them to match their hotel guest master against her registration list, Davis has found a 15 percent to 20 percent deviation. And that only accounts for the hotels she's contracted with.

Based on feedback from the meeting, Shimasaki plans to take her idea to the next level, trying to get as many CVBs to buy into the idea as possible. "The bottom line is that the writing is on the wall," said Shimasaki. "The distribution system has changed and therefore our practices must change."