Utilize the input text as a context reference, choose the right relationship between Canada Post and OTTAWA 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.

OTTAWA - Canada Post is proposing to increase both domestic and international postage rates next year in a move it says is necessary to offset a continuing decline in mail volumes.

Answer: headquarters_location