A Time Series with Forecast Values Is Presented in the Following

Multiple Choice

A time series with forecast values is presented in the following table: $$\begin{array} { | r | r | r | } \hline \text { Month } & \text { Actual. } & \text { Forecast } \\\hline J a n & a & \\\hline \text { Mar } & 12 a & 1.1 a \\\hline \text { May} & 1.15 a & 1.2 a \\\hline J ul & 1.25 a & 12.21 a \\\hline \mathrm { Sep } & 1.3 a & 1.25 a \\\hline\end{array}$$ On this table, a is some nondisclosed value.The mean absolute deviation (MAD)
Is ______% of a.

A) 6a
B) 0.06a
C) 6
D) 0.06
E) 4.8