In deciding to rezone the West Side and open it up to 30 years of redevelopment, the City Council pointedly stopped short last week of endorsing spending on the proposed New York Sports and Convention Center, which would connect to an expanded Javits Center on the West Side. A wise move, a new report just released by the Brookings Institution suggests. A professor of public administration at the University of Texas who studies convention centers, Heywood Sanders, authored the report, “Space Available: The Realities of Convention Centers as Economic Development Strategy.” Mr. Sanders argues that the convention business is in decline – and a turnaround is unlikely to yield much revenue.

“Demand for convention space is not keeping pace with its growing supply, severely limiting the ability of individual centers to accrue hoped-for economic benefits, and ultimately calling into question the value of these large public investments,” writes Mr. Sanders. “Despite their historically dominant competitive position and place as major commercial centers, Chicago, New York, Atlanta, and New Orleans have all seen significant recent loss in convention activity, even as they expanded their convention centers.”

Mr. Sanders’s research casts some doubt on whether the Javits Center’s problem is low capacity. “Despite boosting its convention and tradeshow event count to 70 in 2003 from 62 in 2000 and 61 in 2001, attendance slipped first to 1.25 million in 2000, then to 977,600 in 2001, 931,850 in 2002, and finally 955,150 for 2003. Overall, the Javits’ convention and tradeshow attendance has dropped 32% from the 1997 total,” writes Mr. Sanders.

“For New York’s Javits Convention Center, average attendance at conventions and tradeshows dropped from 20,216 in 1999 to just 13,645 for 2003.”

Part of the story is the decline of technology-related conventions that were popular in the 1990s. New York’s PC Expo, later renamed TechXNY, held annually at the Javits Center, saw attendance drop to a scant 20,509 exhibitors and attendees in 2003, from 75,972 in 2000 and 96,269 in 1998.Mr. Sanders is careful to note that the decline began before 2001, so terrorism wasn’t the problem – and, because 90% of attendees came from the tri-state area, it wasn’t problems with air travel, either.

Yet the city’s convention and visitors bureau, NYC & Company, claims that the Javits Center is disadvantaged by a lack of meeting space. A report by Economic Research Associates, commissioned by NYC & Company in July, claims, “Expansions at competitive top-tier locations have left New York City’s facilities at an increasing disadvantage in terms of facility size, quality, and amenities.” As other cities have renovated their convention centers, “the Javits Center is falling farther and farther behind the competition in terms of overall facility attractiveness.”

According to the ERA report, “The event industry is largely stabilizing and returning to growth trajectory after a significant contraction period of turmoil in 2001 and 2002.” Thus, the proposed stadium and convention center project “is designed to serve a robust, existing demand for event space in New York City. According to a strong consensus of industry experts, this demand has historically been underserved. As such, the project is designed to meet an existing market, rather than create a new market.”

The report finds that “New York is capacity-constrained during the critical months of January through April.” But who is taking up all this space? “Over the past several years, consumer shows at the Javits Center have been growing in terms of size, duration, and share of total facility utilization. From 1997 to 2003, the consumer show share of total utilization more than doubled.” As the report notes, “Typically consumer shows generate relatively low revenues for New York City.”

There’s no question that bringing more tradeshows to New York City would mean more revenue. But the new development project comes at substantial cost, with only speculative benefits. As Mr. Sanders notes, “Almost every convention center in the country operates at a loss, not even counting construction costs or debt.” Meanwhile, the ERA report worries that “New York City is losing market share to other top-tier event cities.” But New York’s politicians might want to pick up a copy of Mr. Sanders’s study and consider whether the city is fighting for a larger share of a dwindling market.