The Billboard 200, published in Billboard magazine, is a weekly chart that ranks the 200 highest-selling music albums and EPs in the United States.
Before Nielsen SoundScan began tracking sales in 1991, Billboard estimated the sales for the album charts from a representative sampling of record stores nationwide, which was gathered by telephone, fax or messenger service.
[1] The data was based on reports from record stores, who ranked the popularity of the best-selling records but did not provide an actual sales figures.
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