Mayo Officials Tout Strong 2012 Performance

Mayo reported Wednesday it took in annual revenue of $8.8 billion last year, with expenses of $8.4 billion.

According to the clinic's annual report, Mayo maintained an operating margin of 4.5 percent which "aligns with the clinic's long-term objectives" of 4 percent to 6 percent.

Mayo added more than 1,000 workers to its payroll in Rochester, for a total of more than 34,000 people who work at Mayo in Rochester alone.

Donations to Mayo dropped for the second year in a row. In 2010, Mayo received nearly $400 million in donations. That dropped to about $320 million in 2011 and about $250 million in 2012.