What is the relationship between Vikram Pandit and Citigroup 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.

Last week, Citigroup Inc's ( C.N ) Chief Executive Vikram Pandit said that he, Chairman Win Bischoff, and senior adviser Robert Rubin would not receive bonuses for 2008.

Answer: employer