1. Perform a moving average forecast.
   1. Experiment with different time windows. Find the best one based on MAPE.
   2. Plot the chosen forecast and actual data overlaid.
   3. Provide MAD and MAPE.

   4. Month Name	Month Number	Sales(thousand $)
      Jan	1	53
      Feb	2	39
      Mar	3	37
      Apr	4	55
      May	5	47
      Jun	6	55
      Jul	7	47
      Aug	8	43
      Sep	9	45
      Oct	10	47
      Nov	11	45
      Dec	12	100
      Jan	13	73
      Feb	14	55
      Mar	15	47
      Apr	16	55
      May	17	47
      Jun	18	43
      Jul	19	45
      Aug	20	40
      Sep	21	23
      Oct	22	33
      Nov	23	31
      Dec	24	44
      Jan	25	40
      Feb	26	46
      Mar	27	50
      Apr	28	51
      May	29	48
      Jun	30	87
      Jul	31	90
      Aug	32	131
      Sep	33	139
      Oct	34	144
      Nov	35	138
      Dec	36	127
      Jan	37	177
      Feb	38	194
      Mar	39	192
      Apr	40	172
      May	41	201
      Jun	42	214
      Jul	43	215
      Aug	44	199
      Sep	45	229
      Oct	46	250
      Nov	47	233
      Dec	48	234
      Jan	49	256
      Feb	50	280