Your grandmother gives you 2400 dollars for your birthday, which you invest in a mutual fund on January 1. On June 1, your fund balance is 7200 dollars, and you then deposit 1100 dollars (which you received for your high school graduation). On the following January 1, you calculate that your dollar-weighted rate of return for the year was 28.5 percent. What was your time-weighted rate of return for the year?