Sales data from cash registers is collected from 14,000 points, whether conventional, mass consumption, or online in Canada and the United States. While this includes the largest distributor, is not 100 representative sample of records of sales, therefore excludes music clubs, as well as many independent distributors and online stores. In comparison the RIAA is more reliable, because all that counts is dispatched, but can not record the sales in real time. The barcode on the back of this most of the CDs or cassettes labeled. When the customer is Canadian or American to buy an album or single, the seller passes the bar coidgo by a scanner. The sale is going to the store's computer and the information is sent to Nielsen Media Research.