Collecting and investing in vintage fine wines has been seen as appealing to many Wall Street bankers. However, the data does not show this investment to always be profitable. For example, in 2003, a banker sold 144 bottles of Chateaux Plonk at auction for a price of $10,341,500. Unfortunately for the the banker, she had purchased it at a price of $12,437,500 in 1999. What was the annual rate of return on her investment in Chateaux Plonk wine over the time period she owned the bottles? (A negative answer should be indicated by a minus sign. Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.) Annual rate of return %