The following time series shows the sales of a clothing store over a 10-week period

Week Sales($1000s) 4 Week error^2 0.3 Forecast error^2 15 16 15.00 1.00 19 15.30 13.69 18 16.41 2.53 19 17 16.89 4.46 DO - ON UI A W N 20 18 17.52 6.15 19 19 18.26 0.54 22 19 18.49 12.35 15 20 25 19.54 20.61 10 21 19 4 18.18 7.96 MSE 7.67 7.70