Only 46,000 race-day tickets have been sold so far for Sunday's Belgian grand prix at Spa-Francorchamps.
Track boss Andre Maes said the number is short of the famous and popular venue's 2009 target of 70,000 spectators, according to RTL Belgium.
"At the moment it is impossible to say if the figure (70,000) will be reached. We don't know what's going to happen in the next days, nor what the weather is going to be," Maes explained.
Last year, attendance of 52,000 led to a 4 million euro loss. 66,000 attended in 2007.
RTL Belgium said 70,000 is the target because it would allow the Spa promoters to break even.
It is said that 3000 tickets were sold within a few hours of the announcement of Michael Schumacher's aborted comeback, but that only about 50 of those asked for their money back.
