I don't think everything has been sufficiently cleared up. Let me elaborate.
You've said that the RIAA counts "sales," however the second quote say that they count unit shipments (minus returns). The first quote says, The audit calculates what product has been shipped for sale, net after returns. It seems that the pertinent question would be "Exactly what sales are they counting?" Now correct me if I'm wrong, but it doesn't seem to say that the RIAA directly monitors sales from the stores that record companies ship to. That is to say, sales of individual records. If Best Buy recieves 1000 records from Sony and doesn't return any of them, and happens to sell 900... will the RIAA report that 900 records, specifically, have been sold? From the wording of the two quotes, it seems like the RIAA would count the number of shipments (1000) minus the number of returns (0) and report a sale of 1000 records in their audit. This would be the net shipment to Best Buy... but not necessarily the amount of records Best Buy has sold. Perhaps you can clarify this.
Also, for anyone interested in how soundscan works...
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Nielsen SoundScan is an information system that tracks sales of music and music video products throughout the United States and Canada. Sales data from point-of-sale cash registers is collected weekly from over 14,000 retail, mass merchant and non-traditional (on-line stores, venues, etc.) outlets. Weekly data is compiled and made available every Wednesday. Nielsen SoundScan is the sales source for the Billboard music charts.
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