How on earth is When I Was Your Man on the list and Locked Out Of Heaven isn't?
Same for Diamonds and Stay.
The former(s) were much bigger.
Blurred Lines
Because their sales figures (Locked out of heaven and Diamonds) were split between 2 tracking periods for IFPI. They probably had like 5mil on each period, which fails to make them chart in either top 10. If they had been on a single tracking period, they both would have been really high on the top 10 singles.
Shipments ARE sales based on how many stores bought the album. IFPI has always been based on how many albums are shipped in a year.
Those numbers are still underwhelming. It won't be anywhere near the IPFI for 2015 because it's selling so poorly now. Katy and Beyonce, however, will make the list again.
IFPI has always been based on how many albums are shipped in a year. 
