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Exhibit 3.8
Enabling the analysis ToolPak add-in

With time series data, we are particularly interested in how the data varies over

time and in identifying patterns that occur systematically over time. A graph of the

data, as in Exhibit 3.9, is our ﬁrst step in the analysis. As the British Anthropologist,

John Lubbock, wrote:
What we see depends mainly on what we look for,
and herein

we see the power of Excel’s charting capabilities. We can carefully scrutinize—
look

for
—patterns of behavior before we commit to more technical analysis. Behavior

like seasonality, co-relationship of one series to another, or one series display-

ing leading or lagging time behavior with respect to another are relatively easy to

observe.

Now, let us investigate the graphical representation of data in Exhibit 3.9. Note

that if many series are displayed simultaneously, the resulting graph can be very

confusing. Thus, we display each series separately. The following are some of the

interesting ﬁndings for our sales data:

1. It appears that all of the product sales have some
cyclicality
except for D; that

is, the data tends to repeat patterns of behavior over some relatively ﬁxed time

length (a cycle). Product D may have a very slight cyclical behavior, but is it not

evident by graphical observation.

2. It appears that A and E behave relatively similarly for the ﬁrst three years,

although their cyclicality is out of phase by a single quarter. Cyclicality that

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