Year I II III IV 2003 5 9 8 8 2004 6 9 9 8 2005 6 10 10 7 20

Year

I

II

III

IV

2003

5

9

8

8

2004

6

9

9

8

2005

6

10

10

7

2006

6

10

9

8

12.   The following table shows the number of homes built by Custom Builders, Inc. in the last four years by quarter. Develop a seasonal index for each quarter using the ratio-to-moving average method. (Use the forms below).

Year

Qtr.

Homes

4-Qtr. Moving Total

4-Qtr. Moving Avg.

Centered Moving Avg.

Specific Seasonal

2003

I

II

III

IV

2004

I

II

III

IV

2005

I

II

III

IV

2006

I

II

III

IV

Quarter

Year

I

II

III

IV

Total

2003

2004

2005

2006

Total

Mean

Typical

Index

Year	I	II	III	IV
2003	5	9	8	8
2004	6	9	9	8
2005	6	10	10	7
2006	6	10	9	8

Solution

Using Excel, we can determine a seasonal index for each quarter using the ratio-to-moving average method

Excel output: