Statistical Analysis with Excel® For Dummies®, 2nd Edition

Chapter 3. Show and Tell: Graphing Data

In This Chapter

• Introducing graphs

• Working with Excel's graphics capabilities

• Creating graphs for statistical work

The visual presentation of data is extremely important in statistics. Visual presentation enables you to discern relationships and trends you might not see if you just look at numbers. Visual presentation helps in another way: It's valuable for presenting ideas to groups and making them understand your point of view.

Graphs come in many varieties. In this chapter, I explore the types of graphs you use in statistics and when it's advisable to use them. I also show you how to use Excel to create those graphs.

Why Use Graphs?

Suppose you have to make a pitch to a Congressional committee about commercial space revenues in the early 1990s.

Which would you rather present? The data in Table 3-1, or the graph in Figure 3-1 that shows the same data? (The data, by the way, are from the U.S. Department of Commerce, via the Statistical Abstract of the U.S.)

Table 3.1. US Commercial Space Revenues from 1990 through 1994 (In Millions of Dollars)

Industry	1990	1991	1992	1993	1994
Commercial Satellites Delivered	1,000	1,300	1,300	1,100	1,400
Satellite Services	800	1,200	1,500	1,850	2,330
Satellite Ground Equipment	860	1,300	1,400	1,600	1,970
Commercial Launches	570	380	450	465	580
Remote Sensing Data	155	190	210	250	300
Commercial R&D Infrastructure	0	0	0	30	60
Total	3,385	4,370	4,860	5,295	6,640

Figure 3.1. Graphing ...