What is the Absolute percent error for period $4$ when Three period moving average forecast method is used:$($Please round to $2$ decimal places for your answer$).$ Do Not convert to percentage, leave as a decimal value.

$\backslash$table$[[\backslash$table$[[$Week or$],[$X$($Time Period$)]],\backslash$table$[[$Time series value$],[$or $Y($Sales$)]],$Forecast$],[1,5\mathrm{.}7,],[8,5\mathrm{.}4,],[3,3\mathrm{.}0,],[4,11\mathrm{.}0,],[5,15\mathrm{.}2,],[-,12\mathrm{.}2,],[7,,]]$