Read this and answer the question. If the question is unanswerable, say "unanswerable".

In late 1994, Marvel acquired the comic book distributor Heroes World Distribution to use as its own exclusive distributor. As the industry's other major publishers made exclusive distribution deals with other companies, the ripple effect resulted in the survival of only one other major distributor in North America, Diamond Comic Distributors Inc. In early 1997, when Marvel's Heroes World endeavor failed, Diamond also forged an exclusive deal with Marvel—giving the company its own section of its comics catalog Previews.

When did Diamond Comic Distributors part ways with Marvel?
unanswerable