What is the relationship between Citigroup and New York City in the context of the input sentence. Choose an answer from: 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.

The Tender Offer Consideration or the Total Consideration, as applicable, for each series per $1,000 principal amount of Notes was determined by reference to the applicable fixed spread (the "Fixed Spread") specified for such series over the applicable yield (the "Reference Yield") based on the bid side price of the applicable reference U.S. Treasury Security (the "Reference U.S. Treasury Security") specified for such series of Notes on the front page of the Offer to Purchase or in the table above, as calculated by Citigroup Global Markets Inc., Morgan Stanley & Co. LLC and RBC Capital Markets, LLC (the "Dealer Managers") at 2:00 p.m., New York City time, on October 14, 2015.

Answer: headquarters_location