It's the biggest sporting event of the year: Berlin 2009 the IAAF track and field world championship. But not only the athletes are competing. The German capital is also hoping to make a few records. Some eight million tourists visit Berlin each year and despite the global economic downturn,the city was able to increase the number of overnight stays in recent months.What kind of economic stimulus can a big event like the World Athletics Championship provide? Our reporter Carmen Meyer takes a look.