Loomis had the longest tenure of any employee in Fortune magazine's history, having joined the staff in 1954 as a research associate and retired on July 1, 2014. In 1966, she coined the term "hedge fund". In 1976, she was appointed to the Advisory Committee on Federal Consolidated Financial Statements. In 1980, Loomis was one of six panelists at the presidential debates of Ronald Reagan and John B. Anderson. She retired from Time/Fortune magazine in July 2014 after a tenure of over 60 years with the company.