Conversation so far:
What was on Brooks and Dunn's greatest hits collection?
Brooks & Dunn's first greatest hits compilation released in 1997 comprised most of their singles and three new songs: Honky Tonk Truth, He's Got You, and Days of Thunder.
When did Brooks and Dunn's greatest hits collection come out?
Brooks & Dunn's first greatest hits compilation was released on September 16, 1997.

Question: How many copies did it sell?
Self-contained rewrite: How many copies did Brooks and Dunn's greatest hits collection sell?