Conversation so far:
What is the album Day of the Dead
Day of the Dead is the twenty-fifth compilation release benefiting the Red Hot Organization.
What artists worked on the album DOD
The performersof DOD  included Jenny Lewis, Matthew Houck (Phosphorescent), Lucius, Will Oldham, Moses Sumney, Sam Amidon, Richard Reed Parry, Matt Berninger, Justin Vernon, Josh Kaufman, Bruce Hornsby, and The National.
What year was the album DOD done?
The DOD compilation was released on May 20, 2016.
Why did The National make DOD with a group of other artists?
The DOD compilation, is a wide-ranging tribute to the songwriting and experimentalism of the Dead. All profits will help fight for AIDS/ HIV and related health issues.
Was the album DOD popular?
DOD was a five-plus hour, 59 track Grateful Dead tribute album is a monument of living history – an image of their golden road branching out endlessly.

Question: How many people bought the album?
Self-contained rewrite: How many people bought the album Day of the Dead?