Utilize the input text as a context reference, choose the right relationship between Stock market and stock exchange from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.
Text: Stock market officials and historians calculate that the Athens stock exchange has been forced to cease trading for at least a day on 14 other occasions since the bourse was founded and started trading in 1876.
user
operator
assistant