Suppose we have the following Treasury bill returns and inflation rates over an eight year period: Calculate the average return for Treasury bills and the average annual inflation rate for this period. (Do not round intermediate calculations. Enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.) Calculate the standard deviation of Treasury bill returns and inflation over this period. (Do not round intermediate calculations. Enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.) What was the average real return for Treasury bills over this period? (Negative amount should be indicated by a minus sign. Do not round intermediate calculations. Enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.)