Toyota Way Fieldbook : A Practical Guide for Implementing Toyota's 4Ps

Collecting data is an important part of the philosophy of building a culture
to stop and fix problems, as described in Chapter 8. The greatest benefit is
gained by recognizing problems in “real time” and correcting them immediately.
Data used to solve problems is interpreted from the perspective of long-term
trends and resolving “systemic” issues.

Building a Strong Supporting Argument

As shown in the above examples, there will be symptoms that go along with
problems. In the case of businesses, the symptoms will be reflected in confirming

Chapter 14. Develop a Thorough Understanding 337

Fabrication Daily Units per Hour

0

12345891011121516

20

40

60

80

100

120

140

Date

Units per Hour

Goal = 36

Fabrication Weekly Units per Hour

0

5

10

15

20

25

30

35

40

1/1 1/8 1/15 1/22 1/29 2/5 2/12 2/19

Week

Units per Hour

Goal = 36

Figure 14-9. Chart with artificially smoothed variation due to scale

Figure 14-10. Chart with artificially smoothed variation by averaging

The chart in Figure 14-10 shows the effect of smoothing by averaging daily
data on a weekly basis. The visual impact is lessened, and the daily variability
inherent in this process will not be seen, thus giving a false sense of stability in
the process.