In November 1996, Nielsen started compiling sales charts, before that, sales figures were provided by The Record from a sampling of retailers. Originally, when the chart was started in 1996, there were 200 positions (with the top 50 being published by Jam!). However, because of the reduced singles market in Canada, only the top 10 positions now appear on the SoundScan chart (SoundScan has a policy that at least 10 copies have to be sold in order to make its singles chart).
Since the early 1990s, single sales in Canada have decreased dramatically, and most songs were not available as commercial singles. As a result, the chart rarely reflected the listening habits of Canadians. In perhaps the most notorious example, Elton John's charity single "Candle in the Wind '97"/"Something About the Way You Look Tonight" stayed in the top twenty for three years. By 2004, sales in Canada declined even further, because of the growing popularity of digital downloading of music. As a result, Canadian sales are not as substantial as they had been before in the 1990s and early 2000s, and singles remained on the chart for even lengthier periods of time. In 2006, most Canadian number-one singles sold less than 200 copies.
Billboard introduced their own singles chart for Canada, called the Canadian Hot 100, on June 7, 2007. It is based on digital download single sales data from Nielsen SoundScan and radio audience levels from Nielsen BDS.
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