Organisers of next year's German Grand Prix say that they will need a high attendance if the race's long-term future is to be secured.
The German Grand Prix dropped off the 2015 calendar as the Nurburgring was unable to fulfil its contract while discussions to hold a race at Hockenheim this year ultimately proved fruitless.
The event will return in 2016 with Hockenheim having been given a provisional date of July 31 for its bi-annual race.
With Hockenheim's race-sharing deal expiring in 2018, Georg Seiler says that the circuit needs to improve on its 2014 attendance, when an estimated 50,000 spectators turned up on race day.
"We have a contract for 2016 and 2018," Seiler explained to DPA.
"We need to have filled grandstands next year so that Formula 1 has a future. We have to say to fans: come to the race next year and secure Formula 1 for Hockenheim.
"Hopefully Nico Rosberg will become World Champion this year. Then we will have two German World Champions - it can't be better than that."