Microsoft Office Tutorials and References
In Depth Information
use? If the answer is yes, then your course of action is clear. Yet, there is a cost to
adding worksheets—extra worksheets lead to the use of extra computer memory for
a workbook. Thus, it is always a good idea to avoid the inclusion of gratuitous work-
sheets, which regardless of their memory overhead cost can be annoying to users.
When in doubt, I generally decide in favor of adding a worksheet.
Place variables and parameters in a central location—Every workbook needs a
Brain . I deﬁne a workbook’s Brain as a central location for variables and parameters.
Call it what you like—data center, variable depot, etc.—these values generally do
not belong in cell formulas hidden from easy viewing. Why? If it is necessary to
change a value that is used in the individual cell formulas of a worksheet, the change
must be made in every cell containing the value. This idea can be generalized in
the following concept: if you have a value that is used in numerous cell locations
and you anticipate the possibility of changing that value, then you should have the
cells that utilize the value, reference the value at some central location ( Brain ). For
example, if a speciﬁc interest or discount rate is used in many cell formulas and/or
in many worksheets you should locate that value in a single cell in the Brain to make
a change in the value easier to manage. As we will see later, a Brain is also quite
useful in conducting the sensitivity analysis for a model.
Design workbook layout with users in mind—User friendliness and designer con-
trol . As the lead designer of the workbook, you should consider how you want
others to interact with your workbook. User interaction should consider not only
the ultimate end use of the workbook, but also the collaborative interaction by oth-
ers involved in the workbook design and creation process. Here are some speciﬁc
questions to consider that facilitate user friendliness and designer control:
1. What areas of the workbook will the end user be allowed to access when the
design becomes ﬁxed?
2. Should certain worksheets or ranges be hidden from users ?
3. What speciﬁc level of design interaction will collaborators be allowed?
4. What speciﬁc worksheets and ranges will collaborators be allowed to access?
Remember that your authority as lead designer extends to testing the workbook and
determining how end users will employ the workbook. Therefore, not only do you
need to exercise direction and control for the development process of the workbook,
but also how it will be used.
Document workbook content and development—Insert text and comments liber-
ally . There is nothing more annoying than viewing a workbook that is incompre-
hensible. This can occur even in carefully designed spreadsheets. What leads to
spreadsheets that are difﬁcult to comprehend? From the user perspective, the com-
plexity of a workbook can be such that it may be necessary to provide explanatory
documentation; otherwise, worksheet details and overall analytical approach can
bewilder the user. Additionally, the designer often needs to provide users and col-
laborators with perspective on how and why a workbook developed as it did—e.g.