S$5$: ADDITIONAL EXAMPLES Forecast Error

Airbnb has collected data on the number of users registered on its website. Past number of users and forecast data are shown in the table.

$\backslash$table$[[$Year$,\backslash$table$[[$Demand$]],\backslash$table$[[$Forecast$],[]],E_t,(E_t{)}^2,(E_t-(\frac{?}{\text{b}\text{a}\text{r}}(E)){)}^2,|E_t|,\frac{|Et|}{D_t}$