Procedure
Ultratop creates charts based on retail record sales of around 500 retail outlets and legal digital downloads. Currently GfK is the market observer of the charts. The chart broadcasts on Radio Contact on Saturdays from 12:00 to 14:00. The combined number of Ultratop chart listeners on the various radio or TV stations exceeds two million every week. To celebrate the 10th anniversary of the charts in 2005, a jubilee book was published. It covered all 15,282 singles from 5,882 artists thus far.
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