In sheet "Figure 7-4", the "Deseasonalized Demand" column has been hard coded with the values of the Trend and Level from "Regression-1". Please add another column and recalculate the "Deseasonalized Demand" by pulling up values from the cells corresponding to Trend and Level from the "Regression-1" sheet. Hence this column should no longer be hard coded.
2.  In sheet "Figure 7-4", please calculate the "Absolute Error" , "Mean Squared Error (MSE)", "Mean absolute deviation (MAD)", "% Error" ,"Mean absolute percentage error (MAPE)" and "Tracking signal (TS)".  
3.  For the winter's method covered in class, Please refer sheet "Figure 7-10" of Tahoe salt case while answering the question. Please explain in detail how the forecast for periods 13, 14, 15 and 16 are calculated. 

Figure 7.4

	A	B	C	D	E	F	G
1	Period  t	Demand  Dt	Deseasonalized Demand (Eqn 7.4)	Seasonal Factor (Eqn 7.5)	Estimate (Eqn 7.6)	Forecast	Error
2	1	8,000	18,963	0.42	0.47	8,913	913
3	2	13,000	19,487	0.67	0.68	13,251	251
4	3	23,000	20,011	1.15	1.17	23,413	413
5	4	34,000	20,535	1.66	1.67	34,293	293
6	5	10,000	21,059	0.47		9,898	-102
7	6	18,000	21,583	0.83		14,676	-3,324
8	7	23,000	22,107	1.04		25,865	2,865
9	8	38,000	22,631	1.68		37,794	-206
10	9	12,000	23,155	0.52		10,883	-1,117
11	10	13,000	23,679	0.55		16,102	3,102
12	11	32,000	24,203	1.32		28,318	-3,682
13	12	41,000	24,727	1.66		41,294	294

Figure 7.10

	A	B	C	D	E	F	G	H	I	J	K	L	M
1	Period t	Demand Dt	Level Lt	Trend Tt	Seasonal Factor St	Forecast Ft	Error Et	Absolute Error At	Mean Squared Error MSEt	MADt	% Error	MAPEt	TSt
2			18,439	524
3	1	8,000	18,866	514	0.47	8,913	913	913	832,857	913	11	11.41	1.00
4	2	13,000	19,367	513	0.68	13,179	179	179	432,367	546	1	6.39	2.00
5	3	23,000	19,869	512	1.17	23,260	260	260	310,720	450	1	4.64	3.00
6	4	34,000	20,380	512	1.67	34,036	36	36	233,364	347	0	3.50	4.00
7	5	10,000	20,921	515	0.47	9,723	-277	277	202,036	333	3	3.36	3.34
8	6	18,000	21,689	540	0.68	14,558	-3,442	3,442	2,143,255	851	19	5.98	-2.74
9	7	23,000	22,102	527	1.17	25,981	2,981	2,981	3,106,508	1,155	13	6.98	0.56
10	8	38,000	22,636	528	1.67	37,787	-213	213	2,723,856	1,037	1	6.18	0.42
11	9	12,000	23,291	541	0.47	10,810	-1,190	1,190	2,578,653	1,054	10	6.59	-0.72
12	10	13,000	23,577	515	0.69	16,544	3,544	3,544	3,576,894	1,303	27	8.66	2.14
13	11	32,000	24,271	533	1.16	27,849	-4,151	4,151	4,818,258	1,562	13	9.05	-0.87
14	12	41,000	24,791	532	1.67	41,442	442	442	4,432,987	1,469	1	8.39	-0.63
15	13				0.47	11,940
16	14				0.68	17,579
17	15				1.17	30,930
18	16				1.67	44,928
19
20	α	0.05
21	β	0.1
22	γ	0.1

Regression-1 Sheet

Intercept	18,439
X Variable 1	524