
Chapter 16
664
Deseasonalized data =
TSCR
S
TC R
ii ii
i
iii
=× ×
In order to eliminate the seasonal variations from the data, we will use the most widely used tech-
nique referred to as ratio-to-moving average method. Example 16.7 explains this technique clearly.
Example 16.7
The number of units produced by a company for ve years for all four quarters of the year is
given in Table 16.13. Calculate the seasonal indexes and deseasonalize the data.
TABLE 16.13
Production (in units) of a company for fi ve years (for all four quarters of each year)
Year Quarter Production
2001
1 2022
2 2100
3 2150
4 2120
2002
1 2200
2 2250
3 2150
4 2340
2003
1 2250
2 2300
3 2350
4 2250