Nielson SoundScan

Nielsen SoundScan is an information and sales tracking system created by Mike Fine and Mike Shalett. SoundScan is a method of tracking sales of music and music video products throughout the United States and Canada. Data is collected weekly and made available every Wednesday to subscribers, which include record companies, publishing firms, music retailers, independent promoters, film and TV companies, and artist managers. SoundScan is the sales source for the Billboard music charts, making it the largest source of sales records in the music industry.

Nielsen SoundScan began tracking sales data for Nielsen on March 1, 1991. The May 25 issue of Billboard published Billboard 200 and Country Album charts based on SoundScan "piece count data," and the first Hot 100 chart to debut with the system was released on November 30, 1991. Previously, Billboard tracked sales by calling stores across the U.S. and asking about sales - a method that was inherently error-prone and open to outright fraud. Indeed, while transitioning from the calling to tracking methods, the airplay and sales charts (already monitored by Nielsen) and the Hot 100 (then still using the calling system) often did not match (for instance Paula Abdul's Promise of a New Day and Roxette's Fading Like a Flower reached much higher Hot 100 peaks than their actual sales and airplay would have allowed them to). Although most record company executives conceded that the new method was far more accurate than the old, the chart's volatility and its geographical balance initially caused deep concern, before the change and the market shifts it brought about were accepted across the industry. Tower Records, the country's second-largest retail chain, was originally not included in the sample because its stores are equipped with different technology to measure sales. At first, some industry executives complained that the new system — which relied on high-tech sales measurement rather than store employee estimates — was based on an inadequate sample, one that favored established and mainstream acts over newcomers.

The Recording Industry Association of America also tracks sales (or more specifically, shipments minus potential returns) on a long-term basis through the RIAA certification system; it has never used either Nielsen SoundScan or the store-calling method.

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