Problem $12-22$ Calculating Returns $[$LO$2,3]$

Suppose we have the following Treasury bill returns and inflation rates over an eight$-$year period:

Year Treasury bills Inflation

$19\mathrm{.}87\%11\mathrm{.}87\%$

$210\mathrm{.}7615\mathrm{.}36$

$38\mathrm{.}489\mathrm{.}69$

$47\mathrm{.}787\mathrm{.}43$

$58\mathrm{.}309\mathrm{.}69$

$610\mathrm{.}6312\mathrm{.}15$

$713\mathrm{.}4916\mathrm{.}34$

$815\mathrm{.}3116\mathrm{.}22$

a$.$

Calculate the average return for Treasury bills and the average annual inflation rate for this period. $($Do not round intermediate calculations and enter your answers as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

b$.$ Calculate the standard deviation of Treasury bill returns and inflation over this period. $($Do not round intermediate calculations and enter your answers as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

c$.$ What was the average real return for Treasury bills over this period? $($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$.,32\mathrm{.}16.)$