The percent change might you expect the average cost of goods and services change between January$1,2018$ and December$31,2018$ is

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enter your response here$\%$

$($Round your answers to the nearest hundredths$$ place.$)$

Hint$$: $$First$,$ calculate the percent cost change for the period January through December for each of the previous$$ years: $2012$ through $2016.$ Second, take the average of these five figures to calculate the average percent cost change.

$($b$)$ The estimated average salary for December$31,2018$ is $$$

$$

$\_\_\_\_\_\_\_\_\_\_\_\_($Round your answers to the nearest hundredths$$ place.$)$

Hint$$: $[($December $2017$ average salary$\backslash$times average percentage cost$$ change$)+$ December $2017$ average$$ salary$].]$