Using the data below, calculate the squared error for the $4$th week. Use the $2$ period moving average to create the forecast.

$\backslash$table$[[$Week$,$Time Series Value$],[1,8\mathrm{.}81],[2,12\mathrm{.}70]]$

$3$

$14\mathrm{.}18$

$4$

$19\mathrm{.}13$