Verizon's CEO has been tracking his mood out of 10 in a spreadsheet every day since 2009, and if he gives himself less than 3, he works alone for the day

• Verizon's CEO Hans Vestman ranks his mood from one to 10 every day to get into the right mindset for work. 
• "If you want to lead other people, you need to start with yourself," Vestman said at a Fast Company event.
• He also drew up a "boss contract" outlining five goals he wanted to achieve when he joined Verizon.

Verizon's CEO revealed that he adopted an unusual strategy to stay at the top of his game at work, including tracking his daily mood in a spreadsheet for over a decade.

Hans Vestman spoke about how he maintains a strong leadership style at Fast Company's Innovation Festival in New York last week during an onstage discussion with Mansueto Ventures CEO Stephanie Mehta.