Why are there 2 different records charts in Belgium?

Search: flanders wallonia singles charts

Why: "Breathless" by The Corrs reached #17 on the Belgium Singles Top 50 (Flanders), but #22 on the Belgium Singles Top 50 (Wallonie).

Answer: Two different regions: Flanders, which speaks mainly [Flemish] Dutch, and Wallonie, which speaks [Belgian] French and German

Source: Wikipedia

The More You Know: "The Ketchup Song" by Las Ketchup was popular in both regions. People in the US apparently heard it, too, but not me.