List of World Top 40 number-one singles of 2013

This is a list of the World Top 40 number-one singles of 2013. The World Top 40 is a chart that combines all the sales of singles of many countries of the World. It is published every week on http://www.mediatraffic.de/previous.htm. For more information see website http://www.mediatraffic.de/about-us.htm The chart is also updated weekly here http://acharts.us/world_singles_top_40.