As of October 20, 2016, Eminem’s “Curtain Call: The Hits” compilation had been certified up to 2x platinum in the United States.
On October 21, 2016, it ascended all the way to 7x platinum.
Confirmed by the RIAA, the certification confirms 7 million in US units.
Each unit is equal to 1 album sale, 10 track sales or 1500 track streams.