1.The data , in the next six Tables, represent Historical Monthly Usage of 6 groups of materials by the AZX Company. Use minitab to :

1.Plot the data and check for stationarity usingautocorrelation and Partial Autocorrelation.

2.Estimate an ARIMA models using theBox-Jenkins approach.

3. Do model checking using the ACF and PACF of residuals, residualsHistogram, Normality plot of Residuals ,Residuals vs Fits.

4.Forecast the monthly consumption for year 2007 using the model identified in 2.

Year Month	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004	2005	2006
Jan	0.00	13.38	64.84	31.61	55.03	46.00	73.96	4.76	125.88	119.86	92.06	46.99	27.20
Feb	0.00	13.23	43.90	25.12	26.25	118.37	96.05	186.89	62.25	53.59	46.32	36.72	86.72
Mar	0.00	38.40	47.92	75.21	80.85	80.28	56.48	67.48	111.29	94.70	85.99	36.54	303.44
Apr	51.14	49.04	39.56	52.44	42.79	46.52	49.26	56.64	77.78	103.23	92.42	39.69	224.46
May	51.85	6.60	18.34	39.91	0.00	0.00	0.00	81.08	88.20	69.86	153.91	105.56	280.63
Jun	29.43	7.74	25.65	40.40	0.00	0.00	108.24	69.06	155.33	90.26	158.04	102.34	148.16
Jul	41.18	15.82	37.95	66.65	0.00	139.03	83.24	105.06	144.62	117.23	178.18	92.79	105.71
Aug	50.06	31.11	29.84	59.48	0.00	87.96	36.32	60.84	99.47	89.82	154.49	77.20	94.13
Sep	49.10	40.68	54.35	44.95	36.26	26.91	26.71	113.22	175.08	85.80	164.28	22.33	81.24
Oct	4.15	50.23	47.65	33.71	97.64	52.57	65.64	74.67	119.19	72.42	62.79	65.90	212.85
Nov	51.99	63.42	24.50	59.62	89.99	163.36	52.97	71.16	109.69	139.78	83.42	74.43	74.23
Dec	42.00	49.33	35.15	57.66	132.71	113.17	80.36	49.15	112.29	65.59	61.47	83.01	112.56

TABLE 5