You are considering investing in a project with the following possible outcomes:

Probability of Investment States Occurrence Returns State 1: Economic boom 15% 16% State 2: Economic growth 45% 12% State 3: Economic decline 25% 5% State 4: Depression 15% -5% Calculate the standard deviation of returns for this investment. Round to the nearset hundredth percent. Answer in the percent format. Do not include % sign in your answer (i.e. If your answer is 4.33%, type 4.33 without a % sign at the end.)