Use the following weekly sales data to create an exponential smoothing forecast for period $13$ sales with smoothing parameter $0\mathrm{.}3($your period $13$ sales forecast should be an integer$).$ Assume first period forecast equals first period actual sales. What is the MAPE for the ES forecasts $($round your answer to $2$ decimal places e$.$g$.9\mathrm{.}89)?$

Hint: copy and paste this data into Excel $($there is no need to type out the data in Excel$)$

Week

Sales

$1$

$617$

$2$

$617$

$3$

$648$

$4$

$739$

$5$

$659$

$6$

$623$

$7$

$742$

$8$

$704$

$9$

$724$

$10$

$715$

$11$

$668$

$12$

$740$

$($forecast$,$ MAPE$)=(706,5\mathrm{.}17\%)$

$($forecast$,$ MAPE$)=(709,6\mathrm{.}32\%)$

$($forecast$,$ MAPE$)=(712,6\mathrm{.}38\%)$

$($forecast$,$ MAPE$)=(710,6\mathrm{.}34\%)$