I want to know the answer to the following question:
For how long did the Northern cod fishery provide a stable economy for St. John's?
All the background I'm provided with is that "St. John's, and the province as a whole, was gravely affected in the 1990s by the collapse of the Northern cod fishery, which had been the driving force of the provincial economy for hundreds of years.". Is that enough to answer the question?
Answer: yes