Definition: Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
Input: P&O European Ferries (formerly Townsend Thoresen), a division of P&O Ferries, was a ferry company which operated in the English Channel from 1987 after the Herald of Free Enterprise disaster, when Townsend Thoresen was renamed P&O European Ferries, until 1999 when the Portsmouth Operations became P&O Portsmouth and the Dover Operation where merged with Stena Line AB to make P&O Stena Line.
Output:
What is the ending year of P&O European Ferries?