Mikkelson Corporation's stock had a required return of 13.50% last year, when the risk-free rate was 5.50% and the market risk premium was 4.

Mikkelson Corporation's stock had a required return of 13.50% last year, when the risk-free rate was 5.50% and the market risk premium was 4.75%. Then an increase in investor risk aversion caused the market risk premium to rise by 2%. The risk-free rate and the firm's beta remain unchanged. What is the company's new required rate of return?